Suggest Remedy For Pain Under The Rib Cage

HI I am sorry for TMI but i have a pain in theback of the left side under my ribcage,and i dont know what it is related to-gas or pulled musculs.It happened right after having sex in a little twisted pose,and when i untwisted and relaxed in about 5 min i felt like i have being inflated there,like when u open vacuum pacage and the air gets in the opening-i felt like that...Cant sleep normally for 2 days beccause of pain.Taking symeticon,tried hot bath,massaging that area,what is it and what i caN DO?