My 10 Month Old Had Fever For 3-4 Days Highest

My 10 month old had fever for 3-4 days highest was 104 apparently he has an ear infection we were treating the fever with Motrin & Tylenol (alternating) they gave him antibiotics a amoxicillin twice a day but I'm noticing that he doesn't have a fever but his body temp is lowering to 96.5, 96.5 & it can be hot in a room & his arms, face & legs seem to feel cold. Could this be a side effect of the antibiotic? And what can I do