Mobile data extremely slow after iOS update 8.1.3

After I updated to iOS 8.1.3, my data speed works like at 2G speed. My phone says its still has LTE, but it's definitely not. Even when I turn off the LTE, and my phone is connected to 3G, it's still incredibly slow. I've also tried restoring the phone, turning on and off data roaming, and of course restarting my phone countless times. I have net10, which runs on AT&T towers in my area. I used to have iOS 8.1.2 before I updated. I'm preety tech savvy, but I haven't been able to fix this. It's extremely annoying and frustrating to have such slow internet since I'm away from wifi for most of the day. Any help?