Credit score and Closing

[Jarmill Walker]

Hi, I saw post regarding a person's credit score dropping and them closing on a house. I have a similar situation where I am closing on a house in 4 weeks and I just saw that my credit score dropped 30 points due to my credit card balances increasing by $1,200. I immediately paid $500 on my credit card and will be able to pay another $400 by that closing date but I understand that my credit score will only jump back up a few points. Will this potentially affect me closing? also, why does my score drop so much because of the $1,200 balance increase but if I were to pay $1,200 to decrease my balance or even more my score would only go up a few points?