Clomid?

Ive been tracking my opks for 4 cycles, which are super long and irregular, and ive never had a positive opk test so I dont think I'm ovulating.. do you think my GP could prescribe Clomid to me (i live in the UK)? And for those who've been on it or are on it, what were/are your experiences? How long did it take you to conceive? Any side effects etc or anything generally that you think I should know before making a doctors appointment to ask about it. Ive researched it a lot but I want to know kind of on a personal level what experience is most likely to happen.