Hi Leanne
I took my first trip with Just You only last year at 34. Age really is just a number and the group were really friendly.
My recommendation is that you find something that interests you and go for it.
I now have my next trip booked. Greece this time on Athens, Olympia and the Corinth coast.
I went to Pompeii last year and thoroughly enjoyed it. You will find that you are never alone unless you want to be and there is usually someone that wants to do the same as you.
Nerves are normal. I didnt really settle until we got to the hotel. Find something that suits you and go for it. You won't regret it I'm sure.
The community is great place to start. Not everyone is on it but for my last trip I managed to hear from a few people travelling with me.
Hope you find a holiday to suit you.
Kind regards and happy travels
Sue