Can you explain me the SR-System?

I dont get it, after I made my placements yesterday I was placed 4 pts below last season, while I got placed like 89-100pts above season 11´s final score, and will get 18-23 pts per win while getting 25-33 last season but I still lose like 27 pts after a lose?? Wth?? Im still having at least 3 golds per match, Im calling, I am as good as always on the frickin payload/objective and get punished in the end?? I mean really? What do I have to do to get higher SR again?? This “>50% Winrate and youll climb” is bs.

The amount of SR loss (in case of defeat) and SR gain (in case of win) is dependent on your personal performance (compared to other players who played the same heros in similar situations) if you are below 3000SR. This modifier is called PBSR (Performance Based Skill Rating).

Google search can give good summaries:

Wow thanks, I know this already, but Im performing better then my teammates, I mean there is a reason for the medals in the end, and get punished afterwards thats my problem!

Edit:
And again after losing almost thirty points if I saw this right for a lose in the next round I got 8 Pts for almost 13k DMG, standing on the pl most of the time. Great job the devs did there with the balancing, Im totally interested in keeping on playing the game. Thx.