Have you tried the Muscle Milk Whey formula? It is lactose free. If you want to get bigger, you definitely have to get more protein in your system! I would say at least your body weight, plus add an extra 30-50 grams of protein. If you end up not being able to take the Muscle Milk, then you just have to get more lean protein in your system like chicken, tuna, fish, etc. You may want to cook your food ahead of time so that you have lunch/snacks for a couple of days.
You can also try and pre-workout formula witn N.O. Something like MusclePharm Assualt I heard is really good. It's supposedly a little different than other N.O. products in that it doesn't give you that intense energy while working out. Instead, it works "under the radar" if you will, and after about a week, you will start to see the results. They are supposedly much better than most products on the market. However, I haven't tried it yet, so I am just letting you know what I've heard. I've used Gaspari's SuperPump Max, and to be honest, it really got me jacked up for my work out and almost immediately saw/felt the results. So maybe do a little research on what you prefer, then make your choice.
Lastly, if you are taking a thermogenic to stay cut...STOP! This is probably keeping you from getting bigger. And since you are already cut, albeit on the smaller side, once you start to get bigger, your muscles will pop even more as you will have gotten the "shrink wrap effect". This basically means that your skin has conformed to your smaller body stature and once you build that bigger muscle mass, your skin will be extra tight around the newly added muscle and you will have an even better definition.
So...with all that said, I hope this helps. More protein, try a N.O. pre-workout product, and stop using a thermo (if you are currently using). Oh, and as far as the creatine, maybe switch to another product just to see if you get a better effect...then cycle on and off of it as needed. Good luck man!!!