Google really mixed my stuff this time

Hello,

I just checked some of my old sites after months and a lot of stuff happened, so I wanted to share it with you, it's kinda interesting

I was targeting rank for 3-5 keywords, each has 200-300k search volume, medium competition
Niche is health related

I started 1st website more than a year ago, did some on page Seo, built some low quality backlinks, made social media accounts, youtube video...
I got lucky, social media got exposure and website started ranking for those 5 keywords, in first month I was in page 1 or 2 for all 5 keywords

I never did anything else for the website, checked it maybe once a month

Today I was bored and went to check on it (after 4 months or so) and Boom! My facebook page which has like 5 status uploads in a year is ranked #1 for 260k volume keyword, subdirectory from that domain is ranked #2, youtube video is #4 and Google plus status #7 or so, main domain is nowhere, literally, I guess it got penalized, but subdirectory from that domain is ranked #2 so I don't really know...

And while I was searching I bump into my landing page which is niche related, I made is few months ago but I never did anything SEO wise on it, it has 0 on page seo, no meta tags, no backlicks, almost no content... it's ranked #8 for 300k volume keyword

I don't know if any of this is understandable, but I just wanted to share, tought it's kinda interesting...