Is it normal for my son to start waking up again in the night? He is 4 months old and used to sleep…

Is it normal for my son to start waking up again in the night? He is 4 months old and used to sleep through the night. Now he gets up 2 to 3 times again. he has been chewing and gnawing on his fists a lot and drooling too. he gets so fussy if he has nothing in his mouth to bite on. he has also been doing this since he got a virus a couple of weeks ago.