Interesting that none of you have suggested Engine problems.

I haven't checked it out by the way, I probably won't until this
weekend.

My reasoning is that so far, it's driving well and the breaks seem
fine. I was going to change the tire and put it back on, but then the
lugnuts were on tight enough that I felt I better not mess with it.

Thanks for all your advice, I'll get it checked as soon as I can, I
hope it survives until then.