7 weeks postpartum

Okay guys so I had my baby girl on January 6th so I’ll be 7 weeks postpartum tomorrow. I had a c section and bled for like 3 weeks and stopped bleeding for two weeks. Well last week I started bleeding again thinking it was my first period back since having her. I didn’t bleed so heavy cause I’m on birth control and my doctor told me I wouldn’t and it lasted like 5-6 days like a normal period would. Well I quit bleeding around Thursday and now today I started bleeding again. I do breastfeed and I’m back having sex with SO. But I’m very confused on to why I’m bleeding again. Anyone have any answers or any advice or comments. Has this happened to anyone else?? Thank you in advance.