I recall having a similar problem to this when I very first started.
Can I perhaps recommend something? If you’re working with an empty map, and you rotate the first few things you drop into the level, you’ll spend the whole of the rest of the time trying to drag things in a direction they don’t want to go 
It’s much easier to leave things ( initially ) at their default rotation and go from there, just working in line with the XY grid. ( I mean if you’re making a room, just leave it aligned on the default axis ).