Tmi bleeding

So I had a c-section on the 16th. At first my bleeding was really heavy but then it got alot lighter (I think because I'm pumping milk every three hours). I actually was able to switch to panty liners today. Well earlier I decided to masturbate. Nothing internal just some clit stimulation. Now I am bleeding heavier and had to switch back to pads. Did I mess something up by getting off or is it normal for the bleeding to flucuate?