Hi Nicambhar
This whole TTC thing is frustrating. Just hang in there.
I temp downstairs, and I find that my temps are higher on average than in the mouth. If you are going to change from one place to another, then do it at the start of your cycle... changing half way through is not a good idea due to that difference.
As to the lack of sleep, well I have terrible sleep patterns. I just try to take the temp after three hours of uninterupeted sleep, and I tend to get a pattern that indicates O.
Also, maybe if you are concerned, you could try OPK's too...
Good luck!!!
xo