today was a bad day. but the part with the truck -

i was driving and noticed the front of the truck sinking. I knew it was at least a flat tire of some degree. I was able to pull off the expressway into a parking lot. Air is all gone. I check the valves stem because during teh summer, the valvestem broke and caused my flat. same thing today, different tire. Anyway, spare had no air so i called AAA. they come and air up the spare, we put the spare on. BUT when we did so, i hand tightened the wheel lugs, but then the AAA person put the truck on the ground and torqued it. Well of course it wasnt tight! luckily when i left the parkign lot there was a tire place right up the corner. (AAA truck had left very quickly) I should have called them back but i drove up to the corner shop. They said the wheel studs could be compramised. what signs would i look for before they break on me, and how much would it cost to replace all 5? thanks guys! and all this because of a valve stem.