Fizz Support Relic Shield

So I've been maining fizz mid lane for awhile now and have found my win rate sky rocket after just a few games of playing him. Today I went into champ select, and hovered Fizz thinking I was mid, I didn't even think to look at the role I was placed in, idk i guess I just wasn't paying attention. It wasn't until the last champ was locked in did I notice that I had gotten autofilled support. My team didn't say anything in chat and the person that was actually mid selected Taric, so up to the point that I actually looked at the fact that i was autofilled support, I thought I was mid and Taric was support.

I then informed my team that I just realized I was autofilled and that I thought I was mid. The taric replied telling me that he is mid and that the yi was his duo. I had no problem with it, I was actually fine with it because im the one who made the mistake, Yi, Taric strat is strong and plus the enemy bot lane was morgana jhin. Jhin is not very mobile and can't escape my all ins without flash and I could also bait morgana snare, that... and I had a tristana ADC who could easily follow up if I all in.

I get into game take relic shield and right off the bat, everything was perfect. Mid got mid fed af, I roamed mid several times and helped Taric and Yi secure kills as well. This was legit the easiest game I've played in a long time. This game put in promos to B3, I've been winning a lot so hopefully I skip B3 and get B2.

Update: I won all my placement games minus the one I had to dodge because my bot lane decided to lock in naut blitz bot lane against a vayne/trynd enemy team comp. Im like... ok You see there team has a shit ton of dps and you think its ok to go naut blitz bot lane? smfh, anyways I won my promos and got promoted from B4 to B2.