experiencing pain in my lower right abdominal side. It started above my right hip , down to my vigina and leg

Hello
I'm a 30 year old woman, married + 2. I had a Caesarean surgery 5 years ago with no complications.

Three months ago, I started experiencing pain in my lower right abdominal side. It started above my right hip , down to my vigina and leg.

Then the pain started to feel next to my belly button. In the three months, I was hospitalized twice. I had urine, stool, blood tests that were all normal.

I had A CT , x-rays that were negative as well. (the ct showed a small amount of liquid in the pelvis. Every month, I have an attack of pain that includes cold and nausea. the attack is a week after my period.

Three gynecologists saw me and said that my ovaries are just fine. a neurologist also saw me and ruled out any problem in the urine.

I have an appointment with a gastrologist next week. I've never had fever, vomiting or anything like that. When I breath deep , I feel better.

The pain feels like stabbing, and cramps but it doesn't feel related to food in any way. sometimes I wake up at night in pain.

Please help me. Is this serious?