tire is a michelin with 10K miles on it
It depends on HOW flat it was for that amount of driving, as well as the condition of the tire to begin with. Excessive flexing of the sidewalls or internal rubbing could have seriously damaged the tire without it looking bad on the outside. I would drive (not on the freeway) to a tire shop, have the tire pulled and visually check it on the inside before going over about 40 MPH.
Yes. You have what is called a slow puncture. You will be fine at low speeds (30 mph, etc), but get it changed ASAP. The last thing you need is a blow-out. This can happen at any time without warning and is likely at high speed, or with a lot of weight in the vehicle. Go to a back street garage and get a part worn tyre - it'll only cost you about ?20 and be a lot safer.
Look around the side wall of the tire, look and see if there is a visible wear mark all around the tire, that is a good indication of the condition on the inside, that wear is caused from the side wall compressing and decompressing rapidly and could warrant a tire replacement. Any wear on the outside indicates wear on the inside. If there is a lot of rubber shavings on the inside replace the tire. That rubber was once part of the inner sidewall and degrades the rigidity of the tire. Hope that helps.
