When did baby stop waking from gas pains?

LO is almost 8 weeks and for the past 4 weeks she can't seem to sleep on her back AT ALL. Within a few minutes she will start grunting, squirming, kicking, pulling her legs to her stomach then wake up screaming and crying from gas pains. She can't nap during the day or at night on her back at all. Only way she will sleep is on her stomach or chest-to-chest on us while we are propped at a 45 degree angle. But this gives me horrible anxiety as I know it is a big SIDS risk and I am terrified she is going to suffocate and I won't even know until it's too late. I'm constantly putting my finger to her nose to check if she is breathing or holding my own breath to feel her chest move when she sleeps on my chest. I want to be able to sleep her on her back without waking up every few minutes from gas pains. When does this get better? I've tried everything from gas drops to bicycle legs to burping and everything imaginable with no success. Any advice or your experience is appreciated!