Ecstacy, alcohol, cigs and weed in the first 6 weeks.

Here is my story. I have noone to ask for help and no clue what to do, please help, please don't be judgemental..if I wanted to be lectured I would go to my parent's house right now. I need real advice..
I am 20 years old, I work 40 hrs a week and I go to college full time. I love to go out on the nights I don't have to be up too early and I was partying a bit too hard the last six months.
I live with my boyfriend and he has a "job" making almost minimum wage and I am a server. We always could use WAY more money of course- but are living pretty well considering.
I was using esctacy a couple times a week and drinking ALOT from about october to the end of november/middle of december. I am not proud of the partying that I did. I stopped because I could not afford it anymore and was feeling the effects- such as weight loss, insomnia and depression. Also, my boyfriend and I moved in together and we decided to save money and to concentrate more on school and work.
of course I was NOT trying to get pregnant...


anyways...I was supposed to get my period December 23rd, but never did...
the last couple of weeks have been one blur of a tired, nauseous and stressed hellhole. but i took a pregnancy test and it was negative...so i just thought it was stress or lack of nutrition because I don't eat a lot.. I am 115 lbs..5'4'' and I eat when I am hungry- which is fine for me, but i realize now..it is not ok if im pregnant..(but i had no idea)
anyways..this weekend i decided to take ANOTHER PT test...and it was pregnant..
took a bunch more in panic and they all were positive.
I just found out that I was PREGNANT and it has pushed me into a very dark place full of conflicting thoughts and reasons to hate myself.


So..
I think I am 4-7 weeks along and before I found out I was pregnant I:


-I drank probably 1 or 2 nights each week, but not much more.
-I smoked ciggarettes before I found out
-I smoked weed to calm down (and replace ecstacy) about 5 days a week for the last two months or so
-Took my prescription for adderol
-Took ecstacy (4 nights- each time 1- 3 pills, but never more than that: so at most 12 pills)


I know it seems like im a horrid person- but I am not. I am very loving and generous. I am not the skum of the world for using drugs- I am 20 and in college. I messed up, yes. But I did not have any idea i was pregnant and I was actually slowing WAY down on chemicals since ironically around my last period.

but i have 6 siblings and a nephew. i have such a maternal knack in my personality and love kids. i want kids someday SO much- but i didnt expect to become pregnant at age 20. i know i am not ready. i know my parents and EVERYONE IN THE WORLD will tell me to get an abortion.
but the second i found out i was pregnant i became disgusted of everything.
i want to kill myself (not literally) for doing any of those drugs. if i would have known i was pregnant I would have NEVER drank or taken ecstacy or weed or anything.
but i cannot bear the thought of an abortion. I know my baby (embryo) has a heart beat. it has gone through the period where it is extrememely sensitive to chemicals and toxins...in a time where i was unaware of its existence.
i dont know what to do.
i dont know who to ask for help for either because i am not sure what to tell my doctor...can i get in legal trouble for confiding in my doctor and telling him the honest truth ab out everything? and if so, is it worth telling him? or will he advise an abortion either way..
PLEASE HELP!