I just bought a pair of Pearl Izumi I-Beams. These are the first pair of road bike shoes that I have owned. The other pair of shoes that I have are Shimano Mtn Bike shoes. The pair of Pearl Izumi's are are a size nine. I can fit into 9's for street shoes, but these seem to cut of circulation in my feet and make them fall asleep while I bike. I was wondering if it is just a matter of breaking the shoes in or if they may just be too small. I bought them last Saturday, and I have only used them on three rides, each ride is about 45mins each. Has this happened to anyone before?

Do my feet have to get used to having just the cleat touching the pedal?

The pair of Shimano's have support around the cleat that sits on the pedal also.

Just to let you know, I have Shimano SPD-M646 pedals (mtn pedals)

Any suggestions as to what it could be? Do my feet just have to get used to the shoes?

Thanks
Andy