Why do I get anxious?

Travelling on the train tomorrow to Plymouth to have a little ‘Christmas’ get-together with son, dil and son’s dad. As I usually have problems sleeping before a journey, I try to get everything completely ready so I don’t have anything to worry about in the night. One thing is picking up my preordered tickets from the machine - what if they’re not working?, what if there’s a long queue and I miss the train? So I’m here 24 hours early to get my tickets. We’ve all agreed on tiny presents. But they still needed wrapping - plus lots of errands. So , a getting stuff done day