Don't feel bad Scatty. What's done is done. Move on but find out why you ate the beetroot. You need to address this. Hopefully you're still in ketotsis.
I've missed shakes before. I'm sometimes so busy I forget, and it's not until the next day that I remember. That's bad, as we need the shakes for our daily supply of vitamins and minerals. Set an alarm on your phone to remind yourself.