Fluctuating score and $$

Hello. I am fairly new on here and still getting the hang of how things work around here. For a post I've submitted, the amount was $44 but the amount I received was $40. Are the certain fees deducted or something? Also, my influencer score has been flucuating. It happened once and I found out that it has been happening with others as well due to some glitches and such. The problem was fixed. But I see that my score went down again. The last time it went down four points. This time, one. I am so confused!