teething or ear infection?

My son has been really fussy the past 3 or 4 days. He has a cold, he is getting 4 teeth at the same time 2 of them are molars. He also has a diaper rash from cutting teeth. I can't tell if he has an ear infection or if it is his teeth. My kids have never had an ear infection so I have no idea what to look for. He doesn't have a fever just really fussy! I just feel like I always over react and take him to the doctor for the silliest things LOL. I give him teething tablets and before he goes to bed at night I give him motrin to help him rest better. What do you guys think?