My last two probation UA's were diluted, what will happen as a result?

I am on probation, and my last two attempts at taking a urinalysis were too diluted to be properly yzed. I have a severe anxiety disorder and suffer from cluster headaches, and as such it was difficult for me to urinate on the spot. I had to drink water until my bladder was about to burst just to be able to overcome it. My psychiatrist wrote a letter to my probation officer, informing her of the situation and my psychological problems, in hopes that they would be more lenient. How likely is it that the court will order that I take a hair follicle test? If not that, what might they do instead?