New to the ranked experience, and got some questions!

Hey there!

I recently hit level 30 and bought my 16th champion to enable ranked queue, and played 6 games today! 1 loss and 5 wins.

So I started looking into the stats and I noticed a mismatch in premades? From what I've been told by friends, it should be equal no matter what. After investigating the logs of my 3 latest matches I found that my teams were exclusively solo players. Following that logic everyone on the other side would be too, correct? One game followed the "rule" I guess, in the other two there were premades. 2-man in one and 3-man in the other (both could be felt in-game by the way the team was playing, coordinating 5-man dives etc.). I found no evidence of premades on my team in either of these last matches, which is why I'm curious if the "premade vs. premade" rule is still a thing or not?

Other than that I like the champion select, but I keep getting my secondary more than my primary (I do adc primary and top secondary). Queue times are also ridiculously short in comparison to back when I played solely normal games, it's insane! 10 seconds and I'm in champ select. Is there any reason as to why I had to wait 5+ minutes for a normal, but 10 seconds max for a ranked? I thought it'd be the other way around honestly.

I originally posted this in the help forum but it was deleted for being in the wrong forum. I thought asking for help was supposed to go in the help forum? D:

Also, if someone can estimate where I'll land if I win say, 50% of my next matches, that'd be cool! :D Thanks!