Bad quality. What about guarentee?

One week ago my wife fitted our car with a brand new set of tyres. The tyre got punctured by a nail and according to them it can't be fix. Apparently there is also a bubble on the tyre. I asked the muslim lady that works there, if there is any possibility of getting a new tyre as per warranty or something. She said that is not going to happen. No new tyre and I didn't even drive with it for longer than a week. I was a loyal customer of that branch for many years and unfortunately for them I will never support them ever again. I had previous niggles with them and still supported them afterwards. This is the last straw though. I am taking my money somewhere else