Going to the doctor sucks.  There's no need to get poked and prodded unnecessarily (Unless you're into that sort of thing.  No judgement here).  The Tricorder from Star Trek is pretty far off.  So, here's the next best thing...

Just take a look at your whiz!  You can tell if you need to see a doctor or if you just need to drink a bit more water!  Hint: If it's foamy...cut back on the laundry detergent.