Really worried

What are signs that I should go get checked? I'm now a month PP and had a c section. My incision on the outside is completely healed but I'm wondering about the inside. Just the other day, I started bleeding like my menstrual cycle is about to start. It's like I'm on it today. I'm getting cramps as well and of course the hot flashes and other things that come along with it. I'm just hoping that's what it is. :( does any mama know of even any signs I should watch for to go get checked??