Should I See a Doctor About This?

I am a 16 year old male who isn't sure whether he has depression or not. It's three in the morning and I am feeling like s**t. My parents are divorced and hate each other. My father is very conservative and religious while my mom doesn't belong to any organized religion and is very liberal. I, along with my pre-teen siblings, live with one parent half the week and the other the other half. My mom is mentally disabled (epilespy and bi-polar) and can be a little crazy. They speak ill of each other at least once a day when we are with them.

I am of two very different ethnicities. I feel as though I am not a part of either race or any race of peoples. I am neither very religious nor very liberal, which brings me constantly into conflict with my parents on both sides.

I have mood swings all the time and can never keep concentrated. One moment I am happy and satisfied with life and the next I want to get out the knife. I am practically a 4.0 student however. I have cut myself before (without anyone's knowledge), thought about suicide and seriously considered trying drugs but so far have been able to resist temptation. I am gaining some weight which is worrying me and if I do gain a lot of weight I think I will explode. I was on accutane to get rid of my really bad acne.

A lot of the time I feel like I don't want to do anything anymore. I can't keep on routine. I can't even keep my hands still (they are always shaking). I don't talk while in the presence of my dad much in fear of retaliation if he disagrees with my opinion on even the smallest issues.  

I feel like it is partially my job to raise my pre-teen siblings seeing as though our mom doesn't always have head straight and our dad can be very mean at times. They rely off of me for a lot of emotional support but a lot of the time I feel as though I can't give all that they need, which for me is really sad. I have no clue what to do. I don't want them believing I am incompetent like my mother or careless like my father. What should I do?  
  

[Emmyjay]

sounds like you've been througha rough patch :( im sorry to hear about the self harm, that is definately something you should get help over. well done for not going down the drugs route, its a terrible rollercoaster to get off. about the weight issure, i wouldnt worry too much about it, can you still wear the same clother or are youhaving to buy new ones to fit into?
the issue with your dad is a big one, maybe he needs to know how you feel, how all your siblings feel too, maybe he just doesnt realise. and as for both of your parents slaggin each other off to you kids isnt right, children will always love both parents, it not fair for them to put thier feelings on you guys! maybe this is worth mentioning to them? they may be so caught up in themselves they just dont realise!
Why dont you feel as though you fit in? how old are you? i dont feel i fit in to any particuar group, but im still finding out who i am, some people dont find out till theyre 40!!! just be who you are now, dont worry about fitting in with parents, or religious groups, do what you want, find out who you want to be, not who someone else wants you to be!
how old are your siblings? all you need to do is explain to them your doing your best, and you will always be there for them, its not your job to raise them, i think your parents are very wrong to make you feel this way, yes your mum is ill, but your dad should just be a man and deal with it!
none of this is medical, but its just emotional support from me, if you dont agree im sorry, im just voicing my opinion, if you wanna get back to me feel free. im always here to chat if you need to.

Emmy