Frompa, you are all set to go. I moved your 20 miles to yesterday's date on your sheet (since that's the only day that has happened so far, I figured it was a safe assumption). Add to that sheet, and you will be good to go! Glad to have you here.
Also, I will PM you a link that should go directly to your sheet. That should help you get a start finding where to enter the mileage.
If anyone else would like a link to their sheet directly, just look at the URL when you are on your sheet, and pay attention to the last part of the url. You will see something like /edit#gid=#########. That link is to your sheet directly. If you bookmark it, it will always take you right to your sheet for the rest of the month.