Mary Clyde...I had the same thing happen to me. My 'low tire' light came on, last Saturday afternoon..or at least that's when I found it...I use a GodyearTire Store here close by..naturally they were closed...I too went to Walmart...ropes were drawn across the pull through tent...and I figured they had all they could take...So I came home..I thought a back tire might look a tad low,,,but not much. I called my daughter and told her if it went flat I would have to call her if I needd anything before Monday. Well... Monday came, the tire looked the same...I went to tire store and they said it had a nail...on the side...I sort of needed back tires anyway...I bought two front tires last summer. So I had them put on the back, and got two new front tires. So I am ready to go. I don't like to run a 'fixed' tire. Stella