*hugs* I know how you feel. Feeding my son solids threw me for a loop! Give me a routine to be tweaked over that, please!
You're doing nothing wrong. It sounds like he enjoys food and perhaps (in fact, I'll bet on it) that the weird looks he's making while chewing are just because it's a new sensation. Having had a kiddo with a really sensitive gag reflex--but with tons of teeth (just to show you that having teeth doesn't mean no gagging
)--here are some things that I did/had recommended to me:
1) Get him used to chewing by using those mesh feeders. These things:
http://www.amazon.com/Munchkin-Pack-Fresh-Feeder-Colors/dp/B000GK5XY2. My DS LOVED to gnaw on some fruit in these...they were wonderful! LO can chew to their heart's content, but basically they're just mashing up the food.
2) Knowing how overwhelmed you're feeling, pick one meal a day to experiment with finger foods/self-feeding. Once you feel confident that you know what he can handle, expand to two meals, three meals, and then snacks and meals.
3) To go along with #2, maybe give him the softened chunks of food during that one meal. Let him explore and play with the food and get used to feeding himself pieces of food. As frustrating as it can be to leave them to it, sometimes it's the best thing (with you close by, of course).
4) Give DS a spoon to use while you feed him with another one. Like with #3, this ability will come with practice. My son was not doing this very well at even 12/13mo...it was just a skill that came with time, exposure, and practice. Btw, a thick yogurt is great for LOs to learn to eat using a spoon since it stays put so nicely.
5) Eat with him if you can to model how to eat. So, you're giving him that sweet potato...maybe you could sit down next to him at the table and make a game of it. Pick up a piece and give to him; have him feed you. That kind of thing.
I was never good with recipes, but Lemonthyme has a nice website. I'll track that down
Overall, just know you're doing a good job and that he'll learn soon enough.
ETA: Found her website:
http://mamacook.blogspot.com/