Usually people say to use the first temp when someone gets up.
Since you went back to sleep and slept for about three more hours, I would go with your normal temp time temp and make a 'note' of the 4:45a temp.
All in all, one temp on a random day, isn't going to make a huge difference in the 'overall' pattern.
ETA: Ignore me, I can't do math. It wasn't three or more hours. derp.