Take the LSAT when you are ready. Since you are not afraid of taking it again you could go ahead with the September LSAT and cancel the score if you know it went south. But in general I would say don't rush things.
Have you considered other schools besides Austin/Waco area? Tough schools, UH and South Texas have generally lower medians, and A&M's law school is on the rise. @vduran1988
I am an internal medicine physician south of Chicago and have a daughter who is an attorney, I was a bit harsh but was angered My apologies I am 59 and not as tolerant