I have a 26X2.20 on the rear of my bike and I popped it about a month ago. I replaced it with a 26X1.95 and it went flat yesterday. Today I went back to the only bike shop in town(if you wanna call it that) and got the biggest tube they had, 26X2.195. Is this going to make a difference?? Should I take it back and get the right size tube from a store in another town? And, could the smaller size tube be the reason why it keeps going flat????