Can anyone explain why I seem to have a faulty laugh mechanism?

This has happen on several occasions over the years, me wet my pants hysterically when something is extremley funny. It's been up very frequently immediately sometimes several times a day within mass quantities and even right after I budge to the washroom. Nothing has to even be that funny anymore, only midly amusing and swoosh! Tidalwave! I am in my early thirties..why is this taking place and how do i stop it?
Answers:

How can I get on to The Pill? Without going to the doctors?

It sounds similar to you have a frail pelvic floor. Have you had children? This recurrently causes vulnerability (as can constipation and various other issues). Try to strengthen it by clenching the muscles repeatedly throughout the course of the afternoon - like you are trying to stop the flow of urine. If you are still concerned or are have difficulty, see a physiotherapist trained in women's health.

It's best to address this issue. Apart from the open social repercussions, you risk more serious complications such as prolapse of your reproductive organs.

When women suffer from water retension & gain mass,does it also mean they are purchase fat?

go see your doctor honey it it a medical problem beside your badder is can be controled though