Really worried about my pregnant cat: sneezing

I asked this question already in the "pregnant cat and kitten care" section, but I thought I should also ask here. I'm worried about Maya, a pregnant feral cat of mine. She came here from the shelter about 4 days ago. She seemed fine at the time, except she was always licking her teeths and nose. It seemed weird to me, but nothing to worry about. Yesterday though, she started to constantly lick her nose and started sneezing. She doesn't sneeze all the time, but she still does it often. Also, she often shakes her head, as if one (or both) ear was tickling or had something in it. Is it related?

I lowered the temperature in the room where she stays (I first wanted it to be hot for when the babies would arrive, but maybe it caused the air to be to dry and made Maya sneeze?) this morning. Should I go to the vet? Could she be sick from the other cats at the shelter? She seemed fine a few days ago and now I'm worried that she is sick and makes her babies sick too when they arrive. Could she be allergic to something in my appartment? Like what?

Please, help me! I know we are not supposed to stress pregnant cat (I think she will give birth in the next week and a half), so I don't want to take her to the vet if it's something normal for a cat to sneeze. But I do want to do everything possible to make her better, so I'll go see the vet if it's what I have to do. What do you all think?

Nobody has ever experienced this type of situation? I called two vets and they won't see her until it's gotten worse. They can't medicate her anyway because she is pregnant. Could it be something else than a rhino?

Since she was at the shelter, an upper respiratory virus is the most likely cause. You might ask the vet whether it would be safe to give her some L-Lysine, which might help if the sneezing is the result of the herpes virus.