For the past 5 to 6 months I have been doing things I would never do.

It all started with id just be tired for a few days and then I would be fine then I would be tired and angry, depressed,for about a week or so. Then id need barley any sleep id be wide awake and I would have more sex, I would smoke pot, I would do the extreme to almost every thing. And again I would get very tired to the point to where I couldn't even put on a happy face for my boyfriend I would sleep all day and not have any energy, I only have sex when he begged for it and I was to tired to say no, I would hate everything like myself esteem would like nothing and when we would do it I wouldn.t let him take my shirt off because I thought I was fat and ugly. And that would go on for a week or so. And then id switch back to being very energetic and wanting to have all the time myself esteem would be at its max and I choose to do very dumb things but id be very mean I would freak out over any thing

This is really starting to affect my relationship and its always happening. I never used to be like this I was a very laid back person and my boyfriend keeps pointing out how I am starting to get worried over stuff I used to just laugh about.I am really starting to freak out and wonder what's wrong with me am I losing my mind
Should I go to a doctor I'm only 18 what could it be
The only thing that comes to mind is that my aunt is bi polar could I be too

Bi Polar is a possibility, and you should probably see a doctor to see if there is anything "fundamentally" wrong with you, but before you do that how about you try changing your routine for a while, to more productive and positive things like working out and doing school work. Regular work, just to see if it can be handled in a less extreme way? Never hurts to try.

Good Luck,

Javi