First of all I'd like to point out I already know there a wide variety of posts covering this issue but I'm wondering whether you could help with my case.
I was messing around with the GPIO pins while the Raspberry (model 3B+) was running (critical mistake). After having created the circuit, I tried running the code but the Pi didn't respond (despite it was running). I restarted it and now it doesn't boot (red light). I have tried burning a new image to the microSD card but it doesn't seem to be working; it has already been a week since this.
I'm gonna be more careful the next time for sure. Anyway, I'd like to know whether there is something I can do or I just should buy a new one.
PD: The Raspberry Pi doesn't seem to have any damage, it doesn't get really hot in any special part, and it makes some noise, the processor gets hot but not as if it was running.
Thanks in advance, Gerard