Relax! I know you're worried, and that can be tough! If he's teething, he might need a little ibuprofen or tylenol. If you think it would help, try giving it to him about 30 minutes before meal time.
Just keep putting food in front of him. If he's hungry, he'll eat it. I wouldn't bother with the baby food. That's easy for me to say, because both of my boys lost interest in it when they were about 8 months old. (maybe 9 months, it's hard to remember). Seriously, whatever food you're eating, just put it in front of him. If it eats it, great! If he doesn't, don't worry about it.
He really will eat if he's hungry. Kids are amazing that way. They actually listen to their bodies and eat when they are hungry and stop eating when they are full!