Checkpoints app help?

so i just discovered the checkpoints app a week ago and now i have 1002 checkpoints. Well today i checked in to somewhere and it gave me 10 points so i thought it would do that from now on. Then i tried to check in again and it only gave me 2. I have seen some people get 5 also. Does anyone know why the number changes? Also if you dont have checkpoints download it and use my referral link bostnmagic. When you use a referral link you get 300 to start instead of 200. Thanks to anyone who can help