An Overwhemled Empathic?

I'm 23 years old and after doing a bit of research I believe I'm empathic. I believe I've always been to a degree, but after being criticized by my peers in grade school for being "overly-sensitive" I tried my best to quash down all of the things that made me seem too "sensitive". However, over the last few years I've found that the feelings I experienced as a child are reemerging and doing so with a vengeance.

I will be writing the following information about me under the assumption that I'm correct in what I believe to be empathic gifts. So, if I'm not empathic or if there is more/less to it any information or opinions that can be provided would be very helpful.

I have since my adolescence found large social situations or areas where there are a lot of people gathered in one place (ie. Parties, malls) to be mentally and physically draining. I've read up a bit on empathic gifts and while it mentions that this is a normal thing for empaths the effect it has on me is overwhelming and I want to know if the following is normal and if there is a way to lessen the effects and if so, then how it can be lessened.

The effect of being around large groups of people can be physically and mentally draining for me, but to the point where I am so drained of energy that I feel like I could drop to the floor and sleep the day away. This exhaustion comes on usually after a few hours around people and it comes on rapidly. One moment I feel fine and the next I'm exhausted. And it isn't the kind of exhaustion that sleep can fix. I've tried to sleep it away and it doesn't replenish the energy I feel I've lost, ever. I just wake up feeling groggy and just as exhausted as when I first laid down. I have found that sometimes meditating can help take the edge off of the exhaustion, but it can be hit or miss. Are there any methods I can stack or mix and match to help alleviate this exhaustion I feel after being around large groups of people?

I find that non-fiction material such as news and documentaries are always a catalyst for an emotional outburst. I think the last time I watched the news was a few years ago after a story about a hit and run where I felt a wave of uncontrollable sorrow while the story was being told and it included an interview of the deceased's friends and relatives. I felt as if my heart was broken with grief and I fell into a sobbing fit.

I also find that I mirror the emotions of people around me. Is there a way to easily separate what is and isn't mine? I know when something is really out of character for me, like aggression. I've gotten a burst of this aggressive anger where I wanted to just get in someone's face and start a fight when I was around someone who was displaying that behavior and I knew immediately that "Woah! That's just not me!"

Something out of character I can shake it off easier than a common emotion for me such as sadness. I've lived with someone who has been very unhappy for a good part of her life--my mother. She's seen a lot of sorrow so growing up I've mirrored that for so long that I don't know if it's mine or hers anymore. Is there anything I can do that can help me differentiate between what is mine and what is someone else's emotion when it's not that obvious to me?

I also have discovered I can sense a person's true nature within a few minutes of speaking to them or being around them. I may meet someone and feel a strong sense of unease or immediate distrust and discomfort with them. I trust my instincts and keep my distance and then a few months later I'll hear from a friend what an awful, horrible person that individual is.

I've always trusted the initial feelings of ease/unease, trust/mistrust, and comfort/discomfort when I meet people and it's always proved in the end that the first impression of either discomfort/unease or trust/ease I get with a person is a reflection of their true character regardless of the way they behave when I first meet them.

The most striking experience I've had with it was one of my history professors at my university. He was a man I truly respected and wanted to get better acquainted with because he seemed like such a funny, interesting person. He invited me to discuss one of my papers in his office before class one day. He was charming and telling me amusing and interesting stories, but within a few minutes of being there I felt this sudden unease. It was stronger than anything I'd ever felt before. I felt as if I had been cornered by a rabid dog and every fiber in my body felt as if they were screaming at me to get away from him. I was so uneasy and scared of this feeling that I was getting that it was so hard not to bolt out of the room and literally run from him. I fought my instincts for the brief period just to finish my conversation with him, but never again did I allow myself to be in a position where we'd be alone together. I found out months later that he was a disgusting creep who had been suspended after forcing himself upon female students who had forged friendships with him.

I'm assuming I'm picking up on good/bad vibes in these initial feelings I get when I meet someone for the first time. Would this be an empathic trait or something else?

I thank you for taking the time to read about me and my experiences. I'd really appreciate any help, advice, and information from the wonderful community here.