Dear Ms. McNamara,
It's possible that you are witnessing the early signs of OCD, though this is not by any means a foregone conclusion. As you are already aware, it's important for you not to project aspects of your own situation onto your son, while at the same time appreciating that conditions such as OCD have a strong hereditary component. What does not support the likelihood of OCD is your son's out-of-home behavior - if it were certain that OCD was represented in his behavior, there would likely be signs outside the family situation as well.
Relative to the bathroom trips, it's perfectly OK to set limits on them, but the quality of the interaction around this is crucial. Try, as I can tell you often do, to maintain your equanimity - anger does not have to surround the interactions. We can be firm in our limits as parents and at the same time maintain our composure. Dr. KDK