Is it normal to have so many trays? Invisalign

I've been on this sight since yesterday looking through mostly every question and it's really helped me a lot! But while I was looking through the forums I started getting upset seeing everyone with 30 under trays while I am stuck with 76. I feel really sad I couldn't be in their positions right now I am only on my first tray and still counting down the days till I can't get them off my teeth which will be in two years.