Please change the fluid and filter, at least.
I would suggest taking to a trans shop and having flush. They have a machine that will remove and replace all fluid, not just what is in the pan.
Park it, take the plates. $
Flushing, changing the fluid, and the filter will not harm it, but by the time it starts to make noise and shift differently, it is probably time to haul it out, clean it and rebuild it. Your problems could be caused by sticking parts jammed with sludge, but a simple flush only cleans a fraction of the inside, there are so many places for sludge to collect. It is very rare to see a clogged filter on an automatic, if it becomes clogged, enough junk has broken loose to destroy the transmission. You should probably decide now if you want to invest in a new transmission and torque converter, or just get a new car. 130,000 is a good run for a transmission, depending on how you drive, many don't last that long even.