Is it too soon or should i wait.

I have a 15 month old son. Hes still breastfeeding up to 5 times a day and during the night. He still doesnt want to walk but gets around well cruising. My husband and i are thinking of having another baby but his family is constantly telling us to wait and for me to take care of myself. Im not gonna lie im not a perfect mother i know its normal but sometimes i cry and get a bit frustrated that i dont know why my baby gets soo cranky sometimes. I know right now hes still teething and has a bit of a cold so i try my best to comfort him but my mother-in-law gives me the stink face assuming im not doing anything about it. I tell my husband that his family is stressing me out yet he doesnt do anything about it.

I dont know what to do anymore. Im 30yrs old i struggled to conceive my son for 10years and now that i know im capable of having babies i want to give him a sibling. Am i wrong for wanting another baby?!