up all night with gassy 4 mo old help!

this has been going on for a month straight. i don't think it's sleep regression, I've cut dairy out and we give colic calm drops. we burp and bicycle legs. I'm up most the night just holding DS while he sleeps because the moment i bend to put him down he jerks and wakes up. I miss the nights I got that 5-7 hour stretch. I almost wish newborn stage was still here because he would sleep through me putting him down. I feel like I can't do this anymore and my husband and I are both sleep deprived. sometimes the only way to get DS calm and to sleep is to nurse. which causes the gas again... repeat the while cycle and then he's up again in two hours, so that leaves me with a out 45 minutes of sleep at a time.

help!