Back again

Me again 🥲 my baby boy is 3mo now, until this last week he was taking 5 ounce bottles very consistently, six of them a day averaging between 25-30 ounces of formula. All of a sudden we go to give him his bottles and he starts fighting and acting like he doesn’t want it after 2-3 ounces sometimes even one. If we go back a little later he may or may not finish it so he’s been closer to 24-28 ounces a day. He’s been a little fussier than usual and keeps shoving his hands in his mouth a lot could it be teething related? There’s no cutting teeth that I can see and he won’t take a tether toy. I thought maybe he was a little stuffy and was coughing a little but isn’t sleeping more than normal in fact he went from 1 hour 30 minute naps 3-4 of them a day and sleeping 8 hours at night taking a bottle and sleeping about 3 more to only sleeping for 45 minutes to an hour nap and we’re lucky if it’s 3 naps and waking more frequently at night. Could this be a sleep regression? A leap? Teething? What would make him less hungry? He’s still peeing and pooping well.