Lost too much postpartum weigh

I didn't gain much during my pregnancy I started at 154 yoyo'd btw 151-162 the entire time (never nauseous) just couldn't keep the weight on... the day I delivered I was 156. I was weighed a few weeks later I was 145 I went for my six weeks yesterday and I'm freaking 136, granted I'm only 5'2 but I fell horribly about being so small. My pants don't fit the same and I hate ppl telling me oh that's fine you look great. No I never desired to be this damn slim. I don't need a flat belly not that I want a big one, but I've never been a stickler about my weight. I like having a little meat on me. I guess it's not helping that I'm breastfeeding as well. -Rant over