Hi. Please note that 1 credit is not equivalent to 1 upvote. The formula is as follows:
1 Credit euqals one 100% Upvote from a person with 10 Steem Power and 100% Voting Power.
So 50 credits equals a 100% upvote from a person with 500 SP and 100% Voting Power. Your specific post got upvoted by fuentesjo3006, apostle-thomas, alalahamed, cgbartow and sipahikara. All their votes together were worth excactly 51,273 Upvote Credits at the time of their voting.
I know it can be a bit difficult to understand this system and I will add more statistic & monitoring features in the next weeks, which hopefully creates a better user experience :)