To elaborate on Bugsy's comment, the speed your game will play depends on several things. How big your level is, how many objects you have in the level, how many characters you have in the level, how many polys said objects consist of, use of dynamic lighting over static lighting, and so on. In this case, the lower those amounts, the faster your game will play.
As Bugsy suggested, you can purchase mods here on the forum that will enhance FPS Creator's performance (they even provide more features such as iron sights for your weapons, duel weilding weapons, and so on). You can keep your level exactly how it is now, but with a mod your game's speed will noticably increase. You can pay $20 for a mod, or $1,000 for a decent computer. Either one will speed up you games.
-Kravenwolf
Success is not final--failure is not eternal.