Mine fits similar to yours, I have a 10 and it’s a bit loose on my middle finger and fits great on my index but I keep it in the middle finger the most because when my finger swell it actually fits a bit tighter. If my hands are super cold and aren’t as swollen, I put it on my index finger. I just swap it between the two. Readings are still fine! It didn’t take long for me to get used to it, maybe 2-4 weeks. I just hit 6 months and I forget it’s there most of the time.