Score fluctuations

EmmaWI88

I've been fluctuating anywhere from 158 to 165. I recently scored 165 on test number 60 (the last one I took). I was feeling pretty happy with the improvement I made (diagnostic 154). But I just took the 72 and bombed back down to the 158. I know a lot of people said at first when they hit the 70s, their scores went down. But I honestly can't see why I would have such a massive 7 points down as I really didn't find the fundamentals between the 2 tests that different. Any encouragement or thoughts on this would be helpful. Has anyone seen this happen to them?

Also if you're wondering why I'm skipping around numbers it's because I give my friend a number range and just have her pick one.