If it's just a small wooden frame Georgian pane, the best thing is to dig out the putty, remove the damaged glass and replace with a new bit.
It's not difficult and you get the new bit of glass cut to size less 2mm all round. Replacing the putty is a bit fiddly, but by the time you've done one pane you'll be expert
It used to be a nice little sideline for 'old school' windies - point out broken panes to people and offer to replace them.