S.C.
First tell your PCP that being a SAHM is a real job AND the most important one in the world! Your DD is so lucky to have you. Two can be a hard age and BUSY! What you need to do is take care of yourself! Do you exercise? get time away from your DH & DD, even for a couple hours? Have a hobby? Getting sleep?
I went through this with my first where it was all about my husband, my son and my house. I didn't get a full night sleep (more than 2 hours at a time) for 5 1/2 YEARS! I kid you not, my oldest woke every two hours for 5 1/2 yrs! Me? I was angry, overweight, empty and a basketcase. With my second I had post partum depression BAD, probably from lack of sleep. I did take medication for a year and then I realized I was no good to anyone unless I take care of myself. Even though it is hard sometimes I try to get up early to go walk (by myself) for 30-45 minutes before anyone else is awake it gives me a better outlook for the day. I also joined the YMCA to go workout while the kids are at school and they have childcare for little ones.
Ask for help from your husband, friends, family to help you get to where you want to be. You've heard the saying "If momma ain't happy ain't nobody happy!"
I am doing this great book right now...Hannah Keeley's Total Mom Makeover. Try to pick it up and MAKE TIME to do it. Good luck and hand in there!