Leaking water or pee?

I went to Walmart after a walk for the first time since I stopped working, I'm 36+5, due July 1st with my first baby! I went pee first thing when we got there. 20 mins later walking down the aisle I felt leaking, felt like period blood (gross I know) but that feeling when you first start your period. I've had back cramps all day, pressure down there and some stomach period like cramps but nothing that was over the top. The cramps have subsided and I'm not leaking anymore but it was worrisome, could I be leaking water? Or do you think I didn't empty my bladder all the way? Normally it leaks again sooner if I didn't empty my bladder this time it took a while to leak after peeing but it wasn't a lot, I slowly dripped fluid for about a minute. As I'm typing this I feel the pain in my back again it's not super painful more like an uncomfortable achyness that won't go away. In a FTM, any advice?