Anyone was fine traveling solo, but lost their confidence after a long time without solo trips? Advice appreciated

Hi, I know it's a bit weird but bear with me please. I lived abroad in a few countries for 6 years, all by myself, did small and big trips alone, all fine. I was young and honestly naive, so i had no fear and just went on the trips without thinking too much. I had a blast with my travel, did everything by myself, being confident and such.

Now, i spent the last decade in my home country, taking trips but not solo, and most importantly, i feel much more aware of how terrible the world could be (trafficking, street violence, scams, harrasment, burglars etc). Because i know better, now i have more things to fear. Which is ridiculous and frankly if i was fine back then, i should be ok now. So, have anyone been through the same situation, and how did you regain your confidence?

I'm planning 7 days trip to France (Lyon, Paris day trip, annecy day trip, Nice, monaco &eze day trip, cannes) this summer, and i used to lived in Italy so hoping it's a nice first step to return to travel solo. I'd really like any advice on both being confidence/staying safe and the trip, thank you.