3g almost useless after using for more than a few minutes

I have a rooted mytouch 3G and I've been using the barnacle tether app for the last few months for internet on my laptop. Just recently I've been playing online poker on my laptop. It worked fine for about a day or so, then things started to get extremely slow, barely being able to load google (taking about a few minutes to load a basic html page)

I don't know if it has something to do with using my phone for a connection with the poker clients or if it's just coincidence with the timing of it, I called T-Mobile and they said there are no problems at all with the coverage in my area and to do a Power cycle which didn't seem to help. Does anyone have ANY idea what could be wrong? Thanks in advance for any help or suggestions.

 

Tmobile slows down your internet if you use over 5gb a month. I really doubt I use that much. I still haven't figured out how to check