Fox Red Curly Sedge is Carex buchananii, and is technically an evergreen (ever brownish-red) plant. Theoretically, it doesn't need to be cut back. If it has some dead blades after winter you can usually pull them out (wear gloves!)

It's often said many Carex varieties don't like being cut back, but I've done it with a few, and they've all come back just fine. I do it, if necessary, any time from now through next month, and I take them down to 3-4".

I cut back my fox red curly sedge early this spring (I planted it last summer - with amazing growth) and now I only have 1 or 2 shoots. Should I be worried that it's not going to make it, or is it a summer grower? Is there anything I can do to help it - I didn't realize it didn't need to be cut back.

Can sedge grass become invasive like Pompas grass?

Some Carex (Sedge) varieties are vigorous self seeders, but there is no general rule that they are all invasive.

I cut down my fox red curly sedge grass and it doesn's seem to be coming back......I did not know I should not cut it down....will it come back or should I replace it??

It isn't possible to predict if the plant will come back, Dar.