[MENTION=52458]jonwvara[/MENTION] Don't be hard on yourself. I work with teams that implement enterprise level solutions. Technology is so complex that even professional technology practitioners get caught out like this. The lost revenue sucks, but could of been much much worse!
There are a few reputation checking options online. The one dropped and lost posted looks good. Regularly check that site but also load your site in all the common browsers (Chrome, Firefox, Edge, and Safari) so that you aren't caught out if a browser decides to flag your site as unsafe.