He's a little young, in my own opinion, to start much other than formula and rice cereal. I'm glad you're making your own food though, jarred stuff is so nasty and is not nutritious in the least.
Get a plastic coated baby spoon, he could be sensitive to metal or find/try one that is very rounded on it's edges.
Perhaps the "food" item is causing the issue? It could be too harsh for him? I imagine you are doing one plain food a week? Seeing if he has any reactions to it? Then adding another the next week or so?
Some foods have acids or things that can irritate babies. The only one I can think of offhand is for much older kids, orange juice. Some kids can't drink it until they're older or they get diarrhea. It's too acidic. I think anything with tomatoes can cause the same thing.