It's understandable that you don't like your foreskin if it doesn't work right. I mean, who likes something that doesn't work right?
Pain is most common during the first two weeks, especially with erections, as the wound around the most sensitive body part heals. However, there should be no sex or masturbation for about almost about a month (to make sure it's properly healed). As for the anesthesia, as with most surgeries you'll probably be told not to eat about 12 hours before the surgery.
However, keep in mind that you can try to fix the foreskin (stretch it) so that it stretches back. That's what I did at around early puberty age and I haven't had a problem since. I wrote about that in the following link, and the nice thing about that is that once it works well you can see if you like it or not (I did):
http://circresearch.googlepages.com/tightforeskin
From a medical study perspective, circumcision does have risks. You can read the studies themselves to see how common the risks are (they give you percentages, for example).
Studies have found that circumcision reduces sensitivity (this article also mentions how it has lost popularity in the USA in recent times):
http://www.foxnews.com/story/0,2933,285532,00.html
And despite being more sensitive, you still last in the same six minute range (average) that circumcised guys do:
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1743-6109.2005.00070.x
Makes masturbation more difficult:
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1464-410X.2006.06646.x
Which makes sense, that's how it was made popular in the USA:
http://english.pravda.ru/science/health/27-03-2006/77873-circumcision-0
Increases erectile dysfunction rates:
http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=14979200&dopt=Abstract%7C
More studies and risks are linked here:
http://circresearch.googlepages.com
Best of luck.