Driving has hurt my leg

No I can't say I have, and I'm 81 with arthritic feet and ankles. Do you think you've been rather tense while you've been driving, after all - if you've been using busses for years it must feel rather strange being in charge of a car all of a sudden?
I'd rest up for a few days, and take whatever's your favourite pain killer, then have another 'go' and see how you feel.
When I reached 80 I asked for a 'refresher course' from a local driving school as a birthday gift from my husband. It was well worth it in increasing confidence, especially with reversing, and bringing me up to date with the highway code.
(I was totally fed up with people wanting me to give up my license just because of my age!)

Well if you haven’t driven for a long while then it’s not surprising your muscles are protesting.

If your seat is not at the right distance from the pedals, or the back is set at the wrong angle, you are likely to feel pain.
Try experimenting with the seat one "notch" away from, or closer to the pedals. having the seat too close to the steering wheel will make the steering seem heavier, and less easy to operate. Sit as far back as is comfortable for your arms. Do not got to the other extreme where you have to stretch, though.
If the seat back is too upright, that may well cause a burning sensation at the baser of the neck; so again, experiment with different settings. But only change one thing at a time.
If the seat height is adjustable, that is another setting that may help you.
Hopefully, you will find settings that no longer cause a problem.

Sorry to be alarmist but could it be a DVT? My nieghbour woke up with a stiff swollen calf and that's what it turned out to be.

look at and feel both legs.
if there is any swelling on one leg, ring 111.

How is your leg now?