I guess it’s hard when one minute you feel like a god and the next you feel like an imposter.
Honestly, that is normal. Even for those of us in other IT industries. If you have been there a year then they trust the work you are doing is correct or they would have had improvement plans.
What you can do is go to your tech lead and ask if he can point you at resources to improve your skills.
As for the pay, remember to job hop every couple years to bump it up to keep ahead of inflation.