I just bought my iPhone last Sunday. Everything has been working fine up until tonight. I've had 3G service everywhere until tonight, my 3G is non-existant at my house. I always had 3G signal, but all night, my phone has downgraded to EDGE and is now on GPRS only. I tried resetting my network settings. No luck. Tried turning the phone on and off, no luck. Should I call AT&T or go get my phone replaced?