I second all of the above post! Peppermint tea and *gentle* (please be gentle) walking is the way to do it! I also found a hot water bottle to hold against my tummy and also my shoulder for the nerve pain helped loads as well.
I looked about 4 months pregnant for a good long while after my trach. If you had pelvic lymph nodes removed like I did then some of it may also be from the lymph fluid backing up into your stomach before it works its way to an alternative route. I made sure to wear comfortable clothes that had soft and stretchy waistbands and stayed away from anything with buttons and zips! Both will sort themselves out eventually!