Uber, Sorry about your finger.
HOPE no muscles or tendons were severed!
Years ago I cut my index finger knuckle clean-off. Plastic surgeon had to re-attach the cartlidge and the tendons on either side. The 12 weeks with a splint and months of therapy, to regain motion, range and strength in that finger was a royal pain. Spent my first semester of college trying to write legibly, left-handed.
Since then. I've been VERY careful not to let the wrench slip when tightening down a freshly sharpened mower blade!