2002 Silverado Brake Issues

Hello! I'm new to this truck forum, but probably won't be posting much, but I ran into a issue. I was out mowing lawns one day to when a chirper went off in the rear disc brakes. I went to Oriley, bought the standard Brake Best rotors and mid grade pads, which are CERAMICS, and proceeded to put them on, when I got them on, I started to drive it and then I heard constant squeak from the left side and squeak when braking on the right. I took them off switched around the pads and made sure they had brake quiet on them, then put them back in. Still squeak. So I found out my right brake caliper was sticking, and then replaced both in the back. Then I found out the right rear brake line was bad, so I replaced that. (All from Oriley, all brake best brand) now both sides constantly squeak after 2 days of driving, and then get louder when I step on the brake. Both rotors have 1-2 lines in them and they only have about 1 week of about 30 miles a day. So not that long. I talked to the guys at Orileys, and they have a very experienced guy I'm going to talk to tomorrow after school. I wanted to get your guys' inputs on this issue.

One separate thing I also did was replaced the rear axle seals, a week ago when I originally did the brakes.

I'm going to get other pads tomorrow to try to resolve this. Either a Wagner Thermo-Quiet Ceramics or the Brake Best Select Semi-Metalic pads. What's your opinion between semi metallic and ceramic, and also about my issues?