I think this is because quick acquisition of links replicates social signals. My guess is it won't rank for very long. I see this type of scenario all the time.
You please keep the record of your back links on an excel sheet rather than depending on google webmaster tools and other tool to check back links as they are not perfect to check all the back links, they even show 404 error pages where you links might have been removed.
Google webmaster tool is show you important back link. But back link watch is not paid version is free tool is not matter that is one back link show you 10 or 20 times same links so don't worry you depend only webmaster tool its gives you perfect and don't confused for this silly reasons.
Number of backlinks depends on the number of webpages visited by any backlink checker crawler, I recommend you to use ahrefs, Ahrefs provide backlink details on daily basis.
Number of backlinks depends on the number of webpages visited by any backlink checker crawler, I recommend you to use ahrefs, Ahrefs provide backlink details on daily basis.