Where did my baby go?

one minute he's the sweetest thing on earth - I just want to gobble him up; the next minute he's a screaming machine and NOTHING consoles him. I swear he screamed for 4 hours tonight. Teething? maybe. Ear infection? maybe. So then I'm left struggling with the decision of whether to drug him up or not. Pacifiers don't help, neither does rocking, singing, or bouncing. In lieu of medication, the only other option is to nurse - so then I worry about starting habits that I'll have to break...ugh. I nursed him to sleep, poor guy.