Internet Usage Question

[ibright05]

I flashed a new ROM on my phone recently and while checking my usage on the Sprint site, I noticed that data usage was practically at 0 when I've been using my phone's connection almost non-stop over the past week (no internet at the apartment). I know I've been having problems with the internet sharing program so I switched back to using PDAnet last night. My question is that while looking in the connections under advanced, my phone is connecting using 'MY ISP', does that sound right or should it be 'Data Network'? I honestly have no clue as to what is should be, I'd rather not touch it but I'm just a bit paranoid when it comes to sprint and I don't want a surprise bill even though I've had unlimited data for years.

Thanks in advance.