Sure I can. I start with the number of sheep I expect: 30, and then count backwards. When I count to -3 I know that I have too many sheep. There is no rule that says counting backwards isn't useful. Any positive number can be represented as a negative number in relation with a constant and remain a perfectly isomorphic model of reality.

Infinities are quite different, given that it is by definition impossible to measure whether something in reality is infinite or not unless you have infinite time.