Teething?

My son will be 15 weeks tomorrow and over the past week or so I’ve noticed a lot a few changes and I am not sure if I should make a doctors appointment or not. The first thing I noticed was that he would wake up frequently in the middle of the night. Usually he would sleep about 3-4 hrs straight in his crib, wake up to eat and immediately go back to sleep. For the last week after an hr in his crib he wakes up whining (eyes still closed) and won’t fully go back to sleep until I break after about 30 mins and put him in my bed. After that he started having an elevated temperature. This with lots of chewing on his hands and drooling I figured was maybe teething but I thought that didn’t start until later? Finally he started decreasing how much he is eating. Up until this week he would eat 7oz bottles every 4-5 hrs like clock work now he won’t really eat past 4-5 every 6hrs! Is this all part of teething? Should I make a doctors appointment? He has his regular check up on December 4th but I’m just a FTM and not sure if I need to be concerned or not.