ok so I've seen all over the place that contractions feel like menstrual cramps and that they can start either low or in the back.

I've never had periods strong enough to give me cramps from them so how am I supposed to know what I'm supposed to be feeling?!

is it like heartburn but lower? is it like muscles pains, sprained ankle or anything like that?

I have had weird heartburn like indigestion all day off and on today but it's not really heartburn...it's more in the middle of my back