2 month old with bad gas.. what can i give her?

I have done the mylicon the gripe water and colic calm. all dont seem to work and she is in such pain. i have done tummy mages and lots of exercise with her, i have also bought pre-mi for her bottles and she still seems to be gy. the drs say she is fine but i know she is not. i have never seen a infant in such pain and discomfort. is there anything else out there I can give her to ease her pain and to help her p the gas and also stop being so constipated?