Does anyone ever feel this way?

Sometimes I get these weird feelings... I'm wondering if anyone has them or something similar to them.

I sometimes feel like something's wrong. In the pit of my stomach, it feels odd. I've been feeling like that often, so I have to ask everyone if something's happening so that I know what's wrong. It's scary, and normally something's wrong with someone. I don't know what's going on this time though.

Another thing is my friends and I are "telepathic". We seem to be thinking the same things at the same time. The thing is, it's not like we're in the same place doing the same thing when we think of it. We'll be thinking of something and then we'll like text each other about it and it's awkward. We also seem to have the same emotions. I'll get suddenly depressed and I'm not sure what's going on. Then I find out one of my close friends is depressed.
Me and my cousin are like attached, sort of like the thing I was explaining before, but when one of us is freaking out the other one knows. It's more exact than with my friends.

Lastly, I seem to have "deja vu" a lot. I dream things and then they seem to happen. It might just be deja vu, but I think it's more.

I'm not sure if these are real or if my mind's playing tricks on me, but they seem real. Does anyone else feel this way or does is it just me. Is this real or make believe. I'm honestly not sure, does anyone else know?