Sleep training working or not??? HELP!!!?

I will try to make this brief....I have a 5 month 1 week old son. For the past 16 days we have been working on sleep training. His sleep had gotten so BAD that he was up every hour to two hours all night long having to nurse to go back to sleep or be rocked. It was too the point I could no longer sleep period as I knew it would take me so long to fall asleep and then he would wake back up. My marriage is suffering, I was beginning to bring the baby to bed (which neither my husband or I wanted to do). I was going to wait until 6 months but couldn't take it anymore. He is 17+lbs and perfectly healthy otherwise. So I have read several books, Ferber's book was what we chose to do with some tweaking. I didn't expect him to go all night without any feeding but now I think that is where the problem arises. My husband had to do the sleep training because I think I cried harder than the baby did. After two nights of crying about an hour (with checks at 3, 5, 10, 15, ect.) before falling asleep, he had learned how to put himself to sleep. He was waking up around midnight, talking a little snuggling with his lovey and back to sleep until 3ish (talking but I umed he is hungry) when I would feed him and put him back down, he would go to sleep on his own. This lasted about a week. When day 8 rolled around he started waking up at 930-11 and crying. Still putting himself to sleep when initially going down though. I checked him for dirty, checked to make sure his teeth weren't hurting (teeths off and on), but I felt like something must be wrong for him to cry now after a week of doing so well. I buckled and fed him, my bad but my heart breaks to hear him cry so I feel like I set us back there but don't understand why all of a sudden he was waking. Now it is hit or miss. Sometimes he is up after an hour, sometimes he only gets up once. My question is has anyone else had this happen? Do you think he is confused as sometimes he gets to eat and sometimes he doesn't? He doesn't act overly hungry when he does but again he has that sleep ociation that I was trying to break to begin with. Should I just swallow the guilt and try to go all night without a feeding so there is no confusion? My heart is breaking when he cries but I cant start feeding him everytime (that's the only thing that will calm him down) he wakes either or we will just go back to where we were. Please only constructive comments and don't belittle or berate me for doing the sleep training to begin with. And BTW he is doing great for naps putting himself to sleep. He is a catnapper though, 3-4 45 minute naps a day. Thanks for any help!!!