Weird no, there's nothing wrong with planning ahead as long as you realize that everything will change. Dreaming about the things we want to do is a great part of life, it makes it bearable at times when things are rough, & it is gives hope. During the war in 90-91, my friends & I had the rest of our lives planned. We were going to go into business together & make a fortune. All we did was plan our futures, it was fun, it killed time, it took us away from where we were, gave us hope that we would indeed all live because we had all of these plans that needed to be dealt with. So plan away, it'll make you think, you might learn at little something & you'll have fun
It is not weird to plan for a trip to England five years before you go, particularly if it is a very big deal for you. You can look at it as some of the life resolutions that everyone makes and they have to plan for it carefully so that the trip is a perfect success.