I had what I thought was a UTI that hung around for about two weeks. It would go almost completely and then flare up randomly. Finally saw a doctor and was told that as I had a fever and slight pain in my flank and groin that it was likely a kidney infection. The doctor was debating on whether to try UTI antibiotics first but then decided to give me the stronger kidney infection ones straight off. I've been on the antibiotics for about four days and today I'm getting stabby achey pains in my flank and groin again, it feels worse than it did before starting the pills. Is it normal for pain to get worse after starting antibiotics or should I go back to the doctor? I'm not getting any burning from urinating anymore, so better in that respect, but the pain is worse. I don't want to waste the doctors time.