Worried?

My baby is 10 months old. Yesterday and today she’s been sucking her thumb ALL DAY. She usually only does it when she’s sleepy. So I don’t know what’s going on.

Also, she has always been a chatterbox (blabbing away) and now she’s been super quiet.

She hasn’t been crying though. And no temp. She feels cold.

Is this normal baby behavior?

Don’t want to take her to the doctor and get her exposed to any thing right now.