2000 Chrysler Noen has no reverse

reverse has just gone in my neon, drives fine but when I put in reverse - nothing? the fluid was very low when i checked (just barley on stick at hot idle), filled it. let it run for a bit then checked again. still no reverse and fluid smells burned.
I think it may need a new reverse clutch or something like that, anyone know what it may be and approxametly how much will it cost to get it fixed???? :uhoh: :banghead: