lol, I've come to realize that you never know what to expect with teething! Sometimes they sleep more, sometimes they sleep less, sometimes you just don't know. It think maybe you could try meds before bed, see if it makes a difference. If it doesn't, then you know it's probably not teething!
What is he like when he is waking? Does he resettle by himself or does he cry and need lots of help?
What time do you go to bed? Is is possible that he is waking because he hears you, but then once you are in bed and all is quiet he sleeps well? I find that my DS will wake once in the evenings sometimes, but after we go to bed he is fine until the morning.
(((HUGS))), I remember pulling my hair out when DS was that age because I could never pinpoint any reasons for waking. There is so much going one, that it's rarely ever one problem. So consider teeth, OT or UT (although I think your routine looks ok), any new foods he might have eaten that are causing gas or discomfort, hunger or growth spurts, and also developmental factors can play in here too - has he started sitting, rolling, crawling, etc.