That's it. I burst into tears in the car today after visiting the dog park. Admittedly I was really tired from a week of moving house and setting up, so definitely over sensitive. Nothing really bad happened. But the "my dog is friendly" people were just very rude to me. And Banjo was freaked out because they were crowding the entrance, letting their dogs compete for the treats I was giving Banjo for using calming signals - and told me off for bringing treats - and what really pushed my buttons was a woman giving me really bad vibes because her pup followed me through the first gate as I left. The pup was nowhere near the gate when I opened it and someone going into the small dog area slowed me down.
I haven't found a good alternative walking spot yet... But we'll keep exploring.