Right, I first started having this a couple of years ago. I noticed that that pains were at their worst when I wasn't bleeding as much, sometimes it even happens mid-period, but mostly on the second day. I tried a lot of pills from the dr (ponstan / mefenamic acid, tranexamic acid) and the gave me high strength codine and paracetamol and told me to take them with ibuprofen. However, this last month it was worse than ever but it's been getting worse progressively with some months worse than others. After tanking myself up with the painkillers, I was still vomiting with the pain (apparantly when you reach a certain degree of pain you vomit automiatically according to one doctor I once saw at a drop in centre when I collapsed in the street). In short though, I had a lot of other symptoms and my new doctor thinks I have endometriosis and can't understand why I haven't been sent off to a specialist before now! So now I'm being sent to a specialist gynae unit. Look up endometriosis on the internet and see if you have any of the other symptoms just in case.