I've maintained my weight for some time now
Well it seems to me like its as simple as not eating enough. Hows your pre workout nutrition also?
I doubt its the sleep, stress can play a factor but I think the culprit here is your diet. However, Lee did make a good suggestion as far as adjusting your routine goes. Mixing it up can net some great results when you stall.
I would wait and try for 110 again next week, but if thats a no go, you can do a few other things. Keep progressing every week still, but just do as many reps as you can at that weight. For example lets say you bump the weight up to 115kg, but can only do it 3 times. then bump the weight up some more and aim for 3 until you get to a weight where you can only do it twice, etc... all the way to one rep's.
You can change the exercise to heavy rack pulls. This would be a good change of pace for you, and allow you to get used to using much heavier weight. Use rack pulls at the normal 1x5 ramping scheme.
I would probably a dvise you to try this first though. Up your intake a little bit every day. Pre workout, eat a big meal something at least 500 cals 45-1 hr before. See if that helps your energy in the gym, you could even get some caffeine in you too, but I would hold off on that. Adjust the rest of your day to compensate for the pre-W/O meal, or if you want to listen and increase your calories a bit adjust less.
Keep us posted on how it goes!
6'3" @213
Squat 1x20x275
press:200, Deadlift:475, Bench:300, P.clean:235, Squat:385
"The only failure that is final is to stop trying to improve"