Hello
I hope I am just being paranoid....but anyone's input would be helpful/I am 6 weeks after my 1st step of two, J pouch surgery....(had it done lapro.) My period ended 4 days ago. Last few days I have a few spots, of brown like mucous on the toilet tissue. Not much I mean very little maybe once a day. Still this brown color I never recall seeing before. I have no other symptoms that I can tell(air,fever).
At what point should I consult my Dr., which Dr surgeon or gyno?
How would they verify if it is the begining of fistula?

It's probably just a little dried blood remnants from your period. I've suggested this before to someone else, but next time you see some on the toilet paper, smell it and see if it smells like stool or not.
Keep an eye on it and give it some time to see if it continues well after your period has ended. It also could be that your body has been out of whack from the surgery and your period and bleeding may be spotty and intermitent for a while.
They can always take a urine sample and see if there is stool in it. Check your temp every now and then and if you have a fever at all, go see the doc.
My family doctor is the one that actually diagnosed mine and then my surgeon confirmed it. Keep us posted. Hopefully it's nothing but it is better to be safe.