Empathy

I believe myself to be an empath, and thus naturally I believe in the skill existing. Many people do not. Many people demand proof. To them I have only one thing to say: I can't prove it. Get to know me. If I text you randomly to find out if you're OK when you feel down, or have hurt yourself, or it seems like somehow, someway, I always know the right thing to do or say, maybe you will start to believe. Maybe you won't. That is your prerogative. I'm not here to change your mind. I can only go by my own experience.
I realised it might be a skill of mine when I was in my mid-teens. It was little things, like my ankle hurting in the middle of class, and later finding out my sister had twisted hers in PE. Or I would be in a really good mood, walk past someone in the street and suddenly just be extremely angry. No midpoint, just instant rage. So I did some research, and alot of self-analysis. I didn't believe it at first. I wanted to be able to prove it to myself. Eventually it just happened too many times, and I began to believe in myself and to trust my instincts. I was usually right.
I think for every person it is different. There isn't a set list of rules or tests to know. For example, much of my reading suggests empathy to be a constant barrage of information that you have to learn to block. Sure, some days it feels that way. But for me, it varies. When I'm positive, calm and together, I find I sense alot more. But when I become stressed, or have to much on my own plate, I begin to shut down automatically. My self automatically protects me until I'm ready. But after a certain point I do become incapable of blocking  and I get overwhelmed by emotions.
I wouldn't say I ever completely disconnect. As I mentioned in my last post, for me it seems to work through links. As I build attachments to people I connect with them. My empathy is in essence an extra sense of the world around me. It is an awareness of the connections between every living thing. It is as much a part of my sensory knowledge as touch, sight or sound. But as I have grown older I have learnt to block it out from choice, or to open myself up. I'm still learning, but it's there. 
If you think you might be empathic, try to focus on it. Start to trust your guts. If your best friend looks like the life and soul of the party but your gut says he/she is miserable, ask. You might just be able to help. Feel a random pain out of nowhere? Look around you. Does anyone appear to be experiencing what you are feeling? If so, trust it. But don't look for solid proof. All you will do is drive yourself mad trying to make things fit.
Lastly, in my opinion, I don't think true empathy is something you can learn. Anyone can learn to empathize from an understanding of events, from experience. But I think true empathy is an innate gift.
I could be wrong. As I said, I'm not here to be a how to guide. But in my experience, the empaths I know of began to experience the gift naturally, not out of training themselves to be empathic. I think if you suspect you have it you will be able to develop it. But if you don't understand what I mean innately, if it doesn't make complete sense to you, your gifts may lie elsewhere. And who knows where that may lead you?