Tantrums Already?!

I'm not sure, but I think my strong-willed little guy is starting to show his "will" now. The newest thing he's doing is, what I call, head-banging. If he doesn't get what he wants in the high-chair (of if we can't seem to figure it out), he throws his head back against the chair or he'll hit his head with hand! He'll also throws his head into me if I pick him up from whatever he's doing and he's not ready to stop. I've already gotten a nice fat lip! The other night, I'm not sure if he just wasn't ready to go to bed or what, but he was almost completely inconsolable! He wanted me to hold him and the minute I'd pick him up, he pushed me away. I'd sit him back on the floor and he'd bang his head on the floor (all the while screaming), then come over reaching for me to hold him and it went on like this for at least 15 - 20mins. I thought maybe his teeth were bothering him or he had an ear ache or something, so I gave him a dose of Motrin, which he took w/o any trouble, but as soon as we got back in his room, it started all over again. I finally thought he was just going to have to cry himself to sleep. But when I put him in his crib, he stood up and started hitting his head on the crib! It was so loud I could hear it in the kitchen! Finally, about 40mins later he was so tired from screaming that he crawled in my lab and almost instantly fell asleep. Every night since then he's been fine to put to bed (thank goodness). I really don't like this new thing and I'm not sure if it's a tantrum-type thing or phase or what to think of it! If it is, I hope he outgrows fast! He's also discovered grinding his teeth....ahhh! I can't stand it! I try not to make a big of it when he does it, but sometimes I can't help it! Anyway, that's what's new and that's my new stressers!