so yesterday i bought herobrine for $25 and now it has been changed $50 http://prntscr.com/b4ku74 do i lost my money?!??!!?!?!?!?!??!!?!?!?!?!?!?!?!?!?!??!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!?!??!?!?!?!?!?!?!?!
When you own a particular rank it shows as the original price. e.g. I own the Legend rank, so it shows as $25 (with the sale) So, no you did not lose any money.
After purchasing a rank, you get a "discount" for the rank after. Buying legend for $50 allows you to buy herobrine for $50. With the sale, herobrine would then be $25. After purchasing, it then shows the regular price after its purchased. If there wasn't a sale, it would show $100 but then show God as $100 as well, because you did not purchase God. But nonetheless, you did not lose money.
They can't simply "take away" your money. That's just not how online shopping work. Also, That explains your problem. With the 50% off sale, Herobrine is 50$ (100$ normally). By buying legend, which costs 25$, you remove 25$ out of that HeroBrine rank's 50$ and 50-25=25. You then bought your herobrine rank for 25$. What probably happened is that the sale temporairly stopped when you checked or you entered the wrong username. I hope this isn't hard to understand... lol