Click in the fields and note the cursor position and how it changes when you press the forward and back arrows. It's possible your field has invisible characters such as a return character in the field.
No extra characters or return, field is quite tight and less than full name of field. I'm just looking at one report layout now. In Layout, two fields are Top 1.486 inches yet in browse/preview they're about 2.5 inches lower on the page.
Aligning two fields, let's say "tops", only works correctly if the tops of the field are in the same (vertical) place. I find this annoying to say the least. If one field is 1" from the top and the second is 2" from the top, then selecting the two fields and entering 1/2" from the top will move the fields, but they'll still have the same relationship to each other in terms of distance from the top.