Haven’t gotten my period

I gave birth in October , my baby is now 3 months only . I got my period in November and it’s already January , I haven’t gotten my period. I’m worried. After I gave birth my doctor gave me birth control, but it seems like I’m gaining weight more and more.

I’ve taken few pregnancy test and it’s all negative

Today my husband and I were finally relaxing he said why is your belly so big .. I’m like I agree, I don’t know why

My belly got flatter after giving birth , today it just popped out of nowhere ..

Should I go see a doctor ??

Wait and take another pregnancy test???

I am breastfeeding my baby