Mid-2013 MacBook Air - USB devices not recognized

Hi,

The USB port on the right side of my MacBook Air is not recognizing devices. I just tried plugging in a USB drive, and nothing happened. The other USB port on the left side seems perfectly fine.

The USB port seemed to be working normally for awhile after I bought it. Problems initially began a few weeks ago, I tried attaching a WiMAX (portable wifi) device using an extension cable. (To be precise, this Amazon 3.0 USB extension cable: http://www.amazon.co.jp/gp/product/B00B3P15M8/ref=oh_details_o04_s00_i00?ie=UTF8 &psc=1) For maybe a day or two, the device showed as connected by USB, but then the light went off. It blinked a little on & off, but now it doesn't even do that. But when I leave this device connected using the extension cable, my internet still seems slightly stabler so I leave it that way.

Did I cause some kind of problem by using this type of extension cable? Do I need to take my MacBook Air to a store to have it checked? Thanks!

Best,

Grace