Well, this is a phenomenon which is reported by some of my patients. You are not the first one. So I will not completely refute it. Though it has not been proved in clinical studies. But theoretically or rather hypothetically speaking, masturbation
MAY lead to increased testosterone
(temporarily), which may stimulate the pilosebaceous unit
and MAY cause an outbreak. As you see there are too many MAYs in this hypothesis. Further, most of the subjects do not report any increase in acne
There are many confounding factors involved when you correlate your acne with masturbation. So it is difficult to accept this theory at this point of time.
It is like, you eat a banana and it rains. The next day again you eat a banana and it rains again. You will be tempted to believe that there is a correlation. But the other thing that you need to check- Is this the MONSOON season?? Am I in Cherapunji?....you know what I mean...
Wish you good health