What Causes Constipation Post Masturbation?

Hello,
I am suffering from frequent constipation which happens right after i masturbate,it's causing me a
lot of problems and is happening since the last 2 years.However,when i resist my urge for masturbation for 4 to 5 days or more, the constipation tendency declines to a certain degree and the bowel passage is more smoother if i consume high fibre food like "Guava" in a greater amount during this period of "no masturbation" but then i again masturbate and it persist for an extended period.And if i masturbate again during this already contradicted muscle period,it extends the contraction for an even longer period.And unfortunately,even when my muscles are already in a contradicted position, i end up masturbating just after 2 or 3 days or so.I want to know if there's a specific yoga posture which relaxes my "pubococcygeus muscle" or is there any other remedy or any other stuff which could help relax the muscle? And i want to know, if it's only my pubococcygeus muscle that contracts after masturbation or there is something more to it?

I really need an expert reply soon.