What’s going on!

Cecilia

So I had a baby two months ago and my period is for now irregular but same flow. I am suppose to start my period today but all that has happened is brown discharge or old blood who knows and it is light. I am cramping like crazy and surprised that all I have done is light brown. Do you think this could be what I think it is or is this normal? And yes my husband and I have had sex serval times but we have used condoms. Opinions needed but please be nice thank you in advance!