The way I am reading what you have said is that you installed TB CFW last night so I assume it worked then?
This morning it does absolutely nothing.
You say it did something very similar when you had a USB Hub plugged in but then worked fine after you removed the Hub?
I am by no means an expert, but if my guesses at it working last night are correct, it sounds more like a power/USB problem to me.
Do as suggested and see if you can get into the recovery menu and try to put a USB dongle etc in with 3.55 FW on it to see if it can actually detect your USB (although by looks of what happens when you press the button this may not work???)