Almost 16 weeks and hard to breathe at night

Sarah
Ok so the past couple of nights I wake up short of breath. When I wake up I realize I'm on my back which I'm not a back sleeper to begin with. I will be 16 weeks on friday, I already have 5 kids so of course I look 7 months pregnant already. Do you think pressure is already on my diaphragm? Anyone else go through this at such an early stage?