Constant pain when urinating

For the past 3 weeks I’ve had nothing but a constant pain when urinating and I keep getting really bad headaches and migraines suddenly. Some times I start to feel sick or dizzy and get pains in my sides. Over the last few days I’ve also noticed my urine is a lime green colour. I’ve been to the doctors but they haven’t found anything unusual so I was wondering if anyone has experienced this kind of problem.