Bleeding at 5 weeks PP?

Me

So I am 5 and a half weeks postpartum. Last week my lochia was yellow and pretty much gone. Last night I started spotting bright red and cramping a little. It feels just like the start of my period, but I am breastfeeding my son & didn’t think it could come back so soon. The bleeding is very light but red. Should I be concerned? Did anyone else experience this? Could it be my period? Thanks!