HELP! Internet sharing speed very slow

[pbg225]

I bought a sprint touch pro the day it came out i have an unlimited data plan and a job as a both attendent which allows me to have my computer and kinda chill which i loved the pro for cause i could just connect and have full usage of the internet, and through video streaming and games i was able to get through my 8 hour shift. Speed was great i did speedtest.net and im not sure the exact results but it was about 1500kbs down and 500 up but recently my internet has been extremly slow i havent done anything to the phones software or changed my location or anything yet my speed is at a lowly 400kbs down and 60kbs up does anyone know why or how to fix this!?