NEED ADVICE !!

Hey mommas, so 3 days ago I had cramping in my lower back and stomach, exactly like period cramps. I’m 7 weeks postpartum . I went to the bathroom and I bled through my underwear and almost my pajamas. The following next two days I had no blood and it’s just a little brown when I wipe. Is my period just slowly getting back into routine or could it be something else ?? I really could use some advice. When my partner and I had set this morning it was still just brown and light. And a clump of white discharge came out on him (even though neither of us finished)

Also my postpartum bleeding stopped at 3 weeks, and I’ve been sexually active since 4

Any ideas ??