From looking at your picture it is possible that you have a female. Females have two lines of nipples up the sides of the body and I'm not sure if I can see some. Males however do not have nipples and their testicles are very obvious, especially in hot weather like we're having. The male has a protuding part at his rear end containing the testicles which can be about the size of a small peanut in its shell
.On the forum we either use the biological name of testicles or 'pompoms'!
The female has a rather blunt rounded rear end and the openings are close together if you look underneath. The males vents are about a cm apart. Females also have a distinctive smell, especially when they are coming into season, which happens every fourth night. They will stand very still with their tail in the air if you rub their rump, but if your's is a female it may not do this as it can't smell a male.
Here is what a male ham's testicles look like:
Here is a female standing when she is in season: