Birth control

SO i have an apt wed to get started with some birth control.....im not sure if i can go back on the same pill i used before or if since i had a baby already i would need something stronger.....i was on ortho tri cyclen lo for like 4 years and never had problems until i missed one week bc of the dr and then started taking it and thats how i got pregnant but anways....what do you guys use?? i wanna get something that i know also wont make me gain any extra weight i deff dnt need that problem too lol =P