If you think the chain is tight, loosen it. If you're new to fixed and think the chain is too tight, then it's probably WAY too tight. The tight spot and the loose spot should both have some play; you just don't want your chain so loose that it will pop off when you hit a bump in the road.

Another helpful check is to grab your wheel and give it a spin (with the bike in a rack or upside down, obviously). The pedals should go at least one full rotation with a decent push. If they stop short, it's too tight.