discontinued my pill for a little

so I stopped taking birth control for a while because it was making me dry and whatnot. I took two pills in one night last week because I wanted to get back on it but the next morning I threw up so I discontinued it again. I took my pill just now. I had a uti and foul smelling discharge a few days ago but I’m not sure if that had anything to do with the pill. I’m fine now, I took prescribed medicine. any suggestions? Is it bad to keep going on and off it? How do I regulate this? when can I have sex again safely?