What Causes Gastric And Intermittent Pain In Ovaries And Abdomen?

Hi! I m 24 yrs old n this month i had my 2nd iui. on 5th of feb i took my hcg injection and we had bed on 7th morning, aftern n evng and 8th mrng and evng. Idont feel any symptoms but from last night (15 feb) i felt something gas forming n streching happening in my stomach and i feel vry mild ovaries and lower abdominal pain sometimes (not continues). What does it mean?