only one outlet in grow room

i have noticed i only have one 120v 15A outlet in the whole room i plan to use the closet for a 250w mh/hps light. i installed a 120v 15A outlet 20A trip GFI outlet to insure safety. my question is can i run the 250w light (2.5amps) a small fan, a 55" led tv,a xbox, and a cable box on the same outlet without any problems? had a fire 10 years ago in my house (electrical) when i was a kid so im kind if spectical about it. the 250w lamp and the small fan will have a surge protector to it as well. do i need to worry? or am i fine.

a 55" led tv probably uses around 400w with the speakers on the tv. then your xbox uses around 200w. so that's 600w at 110v so that's 5.5amps on the safe side. that plus your 2.5amp ballast gives you 8amps. add the fan and say you are at 9amps. i think that is still within your limits for a 15amp breaker. they say you only want to run 75% of the rated load for a breaker so that would 12amps on a 15amp breaker. I would say you could even add a fewSMALL things if need be like timers and thermostats. i wouldn't try to put anything else big on that though.