I work in patient safety. There are many reasons for the order of a theatre list. As people have said, children, people with co-morbidities that may be impacted by fasting or anaesthetic will go early on the list. For daycase procedures, the ones which the surgeon thinks will recover quickest will go near the end of the list, giving the more complex or poorly/frail people more time to be monitored before discharge.
You can usually sip water up until you go to theatre - if you're worried about 'starving' then check your admission info but it may be possible to have some toast or porridge late this evening.
Some surgeons prefer to get complex patients out the way first, some prefer to do the simple cases first. The best advice is not to get all stressed out about it, it won't change anything. When you are admitted and speak to the consultant and anaesthetist in the morning before the list starts you can ask then about your likely position on the list. Please don't walk out as then that is a wasted appointment that someone else may have been desperate for.
I hope you get some good rest tonight and the procedure goes well.