Sorry to hear, that's the worst.
Can you clarify what you mean by "nick" in the pool table cloth? Is it just a white scuff mark (actually a burn) or did an actual portion of the cloth get scraped, thus leaving an indent? Or is the pool table cloth actually torn, as in it is ripped? Is the "nick" right down to the slate/base of the pool table?
Could the "nick" just be a bad "white burn mark"? If it is, see this post about how to fix white burn marks in pool table cloth.
Most pool table technicians I've talked to say that patching pool table cloth is the worst case scenario, and should be absolutely avoided if you can afford a new cloth installation. They said that you should stay away from pool table cloth patching because it introduces inconsistency to the way the pool table plays.
If cloth replacement is not feasible for you, however, you can look at some other options.
If the pool table cloth was torn or ripped on the head spot (where you break from) you could put a "spot" over it and forget it but I fear from your description that's probably not the case. Search this forum for tefco master spots for more info.
Some players with small rips, nicks, and tears in their pool table cloth simply ignore them, and others might try to fix the billiard table cloth with a little glue underneath. But again, that type of repair leaves you with a lump that interferes slightly with play and affects the consistency of the play of the billiard table.
If you can't put up with one of those solutions, then have the table re-covered. Re-covering just the base/slate portion of the pool table is the easiest. I don't recommend trying to recover the rails yourself if you haven't done it before. If you are hiring someone, get the whole thing done.
You could probably find a table mechanic to professionally recover the rails plus the bed/slate with a good grade of cloth for $200-$300.