The regular will b too small (sort).

Hey Katish, it all depends on how you sleep. I've got a sleeping bag my exact height and it's perfect for me. However, I tend to sleep on my side with my body partly curled up, so I'm usually not stretched out to my full height. If you're a back or stomach sleeper, the 5'5" length may be a little short since you're already 5'6". You don't want your feet pushing too much against the bottom of the bag while you're sleeping as that will make them cold.