I screwed up I think

So I’m 2 wks pp, I had to take my son to his first drs visit bc he just got out of the nicu, and I think I way over did it. I had my diaper backpack and my baby in his carrier. It was fine on the way out because I didn’t have to carry everything out to the car, or into the drs because my mil was with me and helped me carry things. But on the way back in she wasn’t with me, and I carried everything. Now I’m having severe cramps and my bleeding is a little heavier than before. It’s been super light since 3 days pp, like we’re talking last few days of your period light. I’d say it’s more like a medium/light flow now. It’s not bright red or anything though. It’s still red/brown.