Sith, so you were circumcised when you converted to Islam at age 18?
If we are to believe the claim that circumcision is carried out for reasons of hygiene, then the foreskin must be a design fault, but strangely enough, the Koran specifically forbids altering Allah's creation in any way, so it would seem Muslims are treading on rather unsound ground with this practice.
"You will not see any flaw in what the Lord of Mercy creates." (Qur'an 67:3)
"Let there be no change in Allah's creation". (Qur'an 30:30)
Yet more evidence that Islam copied the Jews, who make no such excuses.
As for female circumcision, have a look at this.
http://news.bbc.co.uk/1/hi/42914.stm
Apparently Muhammad said that circumcision is a "law for men and a preservation of honour for women", and statements like that lead to some Muslims believing that women must be horribly and barbarically mutilated in this way.
If you want more graphic explanations, you'll have to google it yourself. I can't. The subject makes me physically sick.