Shortness of breath, HELP

Does anyone feel like they are out of breath too often? This is my first pregnancy so I'm not sure. But sometimes I wake up out of breath and I can't get it back. It's like I get lightheaded cause I feel like I'm not getting enough oxygen. I try sitting or laying down, but it just doesn't seem to change anything. Some days I don't feel shortness of breath unless I do alot of work or stand for too long. But other days I feel completely unable to function. I am only 6 months right now. Has any mommy ever needed a breathing mask or an inhaler?