Yeah, I would also tell you to retake it. I got a 16 on my PAT (18 AA, 19TS), and I even contemplated retaking it, but decided not after contacting a bunch of schools and finding out that they won't place that much emphasis on the PAT section. Still, when I went to my NYU interview, as my interviewer was flipping through my file, I noticed a little slip of paper in there, with a bunch of comments about my application (maybe notes that were taken while my app was being reviewed), and one of the comments said "low PAT". NYU is one of the least competative schools, and a 16 was "low" by their standards. I still got accepted there, and 4 other schools, but that made me a little paranoid that if maybe there was some other significant weakness in my app, that 16 PAT could have worked against me. You seem like you have a lot going for you...I don't think your other scores are low...your RC is really good, and they love high RC. Also, if your bio score is decent, you're prob in good shape.
By the way, I don't know about everyone else, but I thought the PAT on the real thing was signifcantly harder than most practice tests. The only practice tests I thought were challenging enough were the ones on Acethedat.com...these will really prep you for the real thing, b/c they are just as hard. Good luck! 🙂