How having my doctor on call on a weekend saved me $1,500

I was doing yard work on a hot summer day. All of a sudden, I felt very, very week and thought I was going to pass out. After struggling to take a shower and drinking lots of water, I started seeing blue dots out all my windows.
I decided to call Dr. Mills before calling an ambulance. He immediately told me to check my blood pressure. Turns out it was extremely low. He told me to eat something salty. After eating a bunch of saltine crackers, my blood pressure was back up and I was feeling much better.
The ambulance would have cost me $1,500 and I would have wasted an entire Saturday at a hospital getting tests so doctors could tell me exactly what Dr. Mills told me in one short phone call.