worked with runners dealing with this, and recovering from this, before. I agree with most of what's already been posted, but I would take it a step or two further:
1) Yes, just go out and run for the fun of it. Keep your pace very easy. Don't even check distances or times. Just enjoy the ability and freedom to go out for a run again. Be thrilled that you can run, that you are running, and that you're healthy.
2) Above all, be patient. Keep the distances conservative and the pace comfortable. Forget the 5k in the fall. Your goal for the first several months should be just to become a runner again.
3) Don't run more often than every other day for at least the first month.
4) Stay off the pavement as much as possible.
5) Substitute swimming for running one or two days a week if you enjoy it. But don't exercise on consecutive days for the first month.
Best of luck, and congratulations on getting this far!