Firstly it is not your fault... you are just learning to be a mother & it is hard work, esp when you are tired
Are you putting your lo down awake & can he fall asleep on his own? If not that might be part of the problem.
Next look after yourself, it is important to all mothers, but more so to BF ones... after all day feeds, burp your lo, put him on the floor on a mat & make your self a healthy meal - sandwich, toast, fruit etc and have a big drink of water before & after each feed. If you don't look after yourself, what message are you giving to your lo!!!
Also don't worry too much if you are feeding a couple of times at night because you are tired, often it is quicker to do so for at least some of the feeds esp if they are at regular times (habit waking). Start by feeding for the 11pm & the 4am & work on the 2am as a non hungry waking...can you settle him by just patting his back? Otherwise try pu/pd... I'm not sure how you do it for a tummy sleeper, I think there was a post on the pu/pd board recently where one mother gave her way of doing it.
HTH