A couple days ago, I had a friend help me do a semi-tethered jailbreak using Saigon and the Cydia Impactor tool. Worked fine, and I was able to use Cydia. However, I added a possibly malicious source to Cydia and tried to download AppCake--after the installation process, the screen went dark (still giving off light), rebooted, and most of my Apple applications were missing. Stuff like the phone app, Safari, settings… I restarted my phone and the apps came back, including Cydia, Saigon, and the other jailbreak apps I had on my phone. And then there was AppCake.
When I tried clicking on the apps, they all crashed immediately. Even Saigon, so I have no idea whether I'm jailbroken or not. Additionally, part of the Anemone theme I put on my phone is still showing. The firmware is on iOS 10.2.1, so the cell service signal is normally five circles. However, they are now bars, like you would find on more recent iOS versions. But the firmware is still the same version. The battery indicator is also screwed up. Aside from those issues, my phone works perfectly fine, but I would like to return to using Saigon and Cydia without fear that it will brick or ruin my iPhone SE. Please help, thanks.
Read more: Partially jailbroken iPhone?