pregnant at 16?

Alex • 12.20.15 E🔒❤️ Mommy to one in heaven ❤️ 16 years old
I've had the implant rod since 2015. My boyfriend and I have sex with no condom and he does not pull out  Not wanting opinions on that decision but I am looking for advice with pregnancy tests. I read online that since I'm on birth control, theres a chance the test would show up negative even if I am pregnant but I don't think that's true. I've gotten sick the past few days and last week for two days I also had a fever. Now yesterday and today I've had a fever of 101.6 as well. Any pregnant test I can get that will show me real results even while on birth control?