Get past that should of it is judgement that leads to no outcomes
Could of is an assumption that did not happen.
Your gift? Let me put it in a way that all who are in this community will read will understand. You are an engineer.
There are close to 9 billion people on the planet. There are roughly 80 million engineers. You don’t get to this level by chance but because you can, your part of the .8% of the people of the world who can build it. You don’t lose your abilities they just get rusty.
My advise to you is stop thinking about what should of or could of or if my dad was here as cold as this sounds. Instead keep pushing. Be what you are. Build something and then sell it-you are an Engineer you can do anything.