My Fiance Is About 28 Weeks Pregnant And Has Shortness

My fiance is about 28 weeks pregnant and has shortness of breath really bad. She uses an inhaler every now and then even though she doesn't have asthma and she'll be okay for about a half an hour to an hour and then she feels like she needs it again. She said she knows she's breathing and she knows she's getting oxygen but she doesn't feel like she's getting enough. She's really jittery and can't stop bouncing and rocking and she said she feels like her heart is racing but i checked her pulse and it's normal. What do you recommend we do?