I used to often find that i needed a shit on the drive over to a punt, in one instance I almost got there and turned around; went back home; had a shit & shower then returned (wasn't late as I was just going to walk in a parlour)
That was in my early days of punting when the nerves were worse, don't really get that now unless i'm perhaps seeing someone new at a location i've not been to before although I do try to make sure i've been a couple of hours before the punt