N.M.
Since I'm not a doctor, I obviously can't diagnose, but I did want to share my own experience.
I am 30 years old and I am nearly positive that I have OCD. I am currently booking an appointment to be officially tested. That having been said...
When I was young, like your daughter I did the EXACT same things. Before I learned to tie my shoes, and my mom would do it (and really even after I learned), I would cry every time because she would tie one and then the other and it wouldn't be as tight or it would be tighter than the first one. So, we would have to redo them, over and over. I STILL have this issue, only I don't cry about it anymore, I just keep retying.
Also, my food could NEVER touch either. In fact, I wouldn't allow anyone to put vegetables on my plate with my food. I would wait until I had eaten everything off the plate and THEN I would have the veggies, because I didn't want the juice to touch my food. I also only ate one item at a time. Once that item was gone, I'd move to the next. I have outgrown this, thankfully.
As for how she feels about her clothes. I did have and still have this problem. My "left" side of my body seems to be "bigger" than the right side. So, my shirt sleeves are tighter on the left than the right, etc. I redo my hair (ponytail) TONS during the day because it's too loose, or too tight, or too much to the left or the right, etc.
Those are just a few minor examples. And, for me, it got worse as I got older. And, I started having the obsessions as well as the compulsions when I was a little older.
This is currently affecting my marriage (not to the point of divorce - I have a very understanding DH). But, it causes irritability. And, I don't adapt well to change either.
Anyway, sorry for the novel, but I would say to have her at least evaluated. I don't think there is any harm in having an evaulation and if it is OCD, then the sooner she learns how to cope with it, the better. My parents didn't know there was anything wrong, they figured I was just a picky kid. It would have been so much better and easier for me, if I had learned long ago about OCD.
Best of luck to you both!