Is it postpartum bleeding or my period?

I’m 8 weeks postpartum, and the postpartum bleeding slowed down to brown and stopped since about a week and half ago. Started having sex since the last 3-4 days (was cleared at my 6 week appointment) and today I’m getting a medium amount of bright red bleeding the whole day, so I’ve been wearing a pad.

Maybe a dumb q, but is this my period, or the postpartum bleeding coming back up, or is this from having sex the last few days (I didn’t bleed at all the first few times, it just started today!).

I don’t have cramps, I’m currently not on bc, I had a c section and am exclusively breastfeeding. TIA!