Short of breath..

I'm 7 weeks pregnant with baby #2. My son is 14 months old and still has problems sleeping throughout the night. He's been congested these past few days, and last night was especially tough. I woke up feeling short of breath, not able to take a full gasp- when I tried it sent a cold tight feeling down the centre of my throat to the top of my chest. It's not as bad now, but still there. I've been trying to take it easy but it's so hard with a little one running around. Any suggestions?