Don't worry you won't be alone. A lot of people don't seem to be aware of this forum, I really think that Just You needs to give it more pubicity as it's a great tool for customers.
I'm sure that each and every one of us had some doubts, worries and concerns when going on our first trip, I know I did, I was terrified!! But rest assured you'll be well looked after, have a great time and will soon be looking to book your next holiday.
Make sure to put you JY label on your hand luggage as well as your checked in case, that way others on your trip can identify you and will say hello, but if you spot them first then do say hello to them, don't be shy.
And please do a review when you return, it's a great help to other potential travellers and interesting for us all to read about other holdays. I've only booked my next trip (Andalucia) because of reviews on here.
Happy travels
Rose