Routine intense upper abdominal pain around ovulation

i have been searching on the web for years trying to figure out what this could be but ive had no luck or come across anyone who has experienced this. I’ve been suffering from upper abdominal pain that is quite routine, as in it usual comes at the same stage of my menstrual cycle (the last 2 week period/just after ovulation) and it usually starts at the same time 3/4pm, and it lasts 2/3 days. Pain killers do not help it the only thing that takes it away is sleep, but like I said it comes back at the same time. I havent been able to connect any dots with food/drink or medication. It is incredibly painful the worst pain being upper middle abdomen, but it does expand throughout my abdomen and back. That upper middle bit also gets very hard and swollen. Ive been to guiney and they couldnt find anything out of the ordinary, although at the time I thought it was normal to have the pain upper, and have just recently found out that ovulation pain should be lower, seems obvious now haha but dont judge, so Im going to need to go back to my gp and specify its all upper incase I have wrongly linked it to my menstrual cycle. I’ve been suffering with this for about 10 years, im 21 now and I can remember experiencing this pain months before I got my first period. Has anyone experienced this or know what it could be?