Sounds like the clutch cable may be adjusted too tight. Back off on the adjustment a little at a time (about 1/2 turn) until it feels right. Always make adjustments when the bike is cold. If it begins to slip you either went too far or there is another problem.
Look at your owners manual for adjustment procedures, if you need a manual log on to the Polaris website and download one.
Every day is a good day to ride. Some days are just better than others.
2010 Cross Country
Vic Performance filter, D&D, ATW, VFC III
2006 Vegas (sold)
2003 Shadow 1100C (sold)
Various other bikes all the way back to 1968.