Question about elliptical..

Okay, so everyime I try and figure out how much I burn, I get completley different answers. I'm kind of a newbie to exersize (Well, I havn't in quite awhile anyway..) And today, started off with 20 minutes on our home elliptical.

A little background info is I'm a 14 year old girl, I put in I'd say around moderate effort (Doing level 1, then randomly sometimes switching to level 2) and I am recovering from an ED, but I don't know if that would effect anything. Oh, and I'm 5'2.5, weighing around 103 now.

So my question is, how many calories do you guys think I burned? And yes, I know theres exersice calculators, etc, but I tried them, and there all different. So I'm really stuck here, and help would be appreciated, thank you!

anyone know?

Use this website, but enter it at light effort.

Okay, I did that and it said 123? Idk still what to belive, but for now I'll just guess around 100 then.

The only way to know exactly is to be hooked up to a machine the monitors several body functions while doing the exercise. This really isn't feasible in a home or gym environment. So machines have you enter your age and weight and have heart rate monitors that give you an educated guess. Use that or this website as a gage. Each time try to match or beat your last time. To try and figure exact numbers will only drive you crazy. The machines and/or website are a close enough estimate to get you headed in the right direction.