You are not alone. I have heard similar stories from others. They sold their BTC too early. I also have a story of 7 years of cryptocurrency. I have used BTC as a payment method a lot of the time and I caught some BTC, which was earned from buying / selling digital products. However, I spent BTC at that time. I could have made a lot of money if I had kept BTC.
If you've been in the space for as long as you say you have then it's quite weird to hear you say you've used it and look back and say you should have kept it.
Newbies tend to say it but we all know that if we don't use it and everyone just holds, BTC would never go up in value. You've been through 2 past rallies and now in third. Surely not the time for regret?