Welcome Baby, it does sound as though we are in a fairly similar situation. To be honest I have just been eating lots of naughty things in addition to my normal meals, the easiest things for extra calories I've found are muffins, fudge (50 calories in a small piece), adding cream to mash or making creamy pasta sauces, along with meal replacement shakes like complan after a full meal especially if you make it with whole milk (think it works out about 350 calories). I feel like I am constantly eating but it is slowly going on.
Sometimes I too think we should have started trying sooner as we have been married for years but we were too busy just enjoying our 20s, and it was always the plan to start trying as soon as I got to 30 as assumed it would happen straight away, I do sometimes regret that a little now. 
Wow Friendly, a 2hr train journey, you are definitely dedicated. x