Suppose I float in a dark part of space (no incident radiation source), after I have been displaced from my spaceship. I have my pressure suit but I have lost all power (no more heat source, no more fresh oxygen). How long can I stay alive? Will I freeze or suffocate first? Does it help me to move wildly (to generate heat)?

Base Assumptions:
 - me and the air in my suit is initially at normal body temperature (310 K, 37°C)
 - the temperature of space around me is background levels (2.7 K)
 - 0.2 bar pure oxygen suit environment **OR** mixed gases (78% $N_2$, 21% $O_2$)

(editors note: significant change in question wording from original)