When should I test?

Hello all! I recently went to my gynecologist on the 3rd because my last cycle was only 2 days and tested neg sadly. So I figured It was back to the drawing board... but yesterday I started spotting a very light color today its a little pale redish brown thats a little grainy looking (t.m.i) but my cycle is supposed to start soon too so i dont know if im just getting excited for nothing or could we have a little potato baking. Advice greatly appreciated 🙂