Placement matches

Hi I have a question about the ranking system.

Going through these forums, I was completely scared to touch the ranked queue. There were several horror stories about the placement matched which I hadn't started. I played the first 2 games and ended up losing both. I kept playing and playing over the span of a couple months and ended up with 3-5. at that point, I was ready to accept the fact that I may be in silver. I played the last 2 games, won, and ended up in Plat 5. At thag moment, I was completely confused. I thought that Riot had done a soft reset and due to the fact that I was Gold 1 last season, I didn't expect to get an even higher rank. What has surprised me even more is the fact that apparently they did a soft reset so what gives?

Why am I a higher rank? Im left utterly confused.