If Flex Q Placements were wrong, why is my rank still wrong?

Hello guys, Im here to rant to you and I want your honest opinion about this new 'Flex Q.' Today im going to share the wild tales of my Flex q placements....

I have won 7/10 games.. all were people of higher ranking than me... and by high rank I mean highest being Diamond 5 and I was silver 4.... 7/10 placement got me Silver 4. Since then I have lost maybe 9 out of 10 games after placements but these guys mind you are gold, plat etc. So obviously not Diamond material but I damn sure can beat some. Anyways.. So the 'potential fix' by Riot Games states if I play an additional game, that my placement would be fixed. Mind you my placements 7/10 against Gold+ brought me silver 4...I get Bronze III ...... BRONZE? I had basically a perfect game just now, and Riot decides im Bronze worthy.... Riot in what way shape or form is this right? How am I Bronze if I myself have beaten higher tiers than me. This is not even acceptable anymore and I want some clarifications.... Do games after my placement count towards my rank? Why is it so low compared to my friends? If you lose against Diamonds would they still count after placements? Riot answer me -_-