Postpartum period?

Caysi

So I am nearly 4 months postpartum and I had my period 11/23-11/28 and the last couple days I'm bleeding again? Not heavy like a period but enough that I've had to throw 2 pairs of underwear away and I'm having to wear liners. Is this normal? I thought it was breakthrough bleeding but I didn't think that last days at a time. Has this happened to anyone else?