+1 to texases’ comment.
Also, in case you were not aware of it, by “holding it in gear” you accelerated the wear and tear on the transmission’s synchronizers, and possibly the shift linkage and other internal parts as well. In other words, you should not have driven it as you did, but that is all water over the dam at this point, so to speak.
When your mechanic inspects the trans, he can also inspect the clutch plate in order to see its condition as well.