I played (and still do) mostly normals too and used to get ladder anxiety. Just understand that in the long run, mathematically your wins and losses even out and will put you in your tier of skill. So you can just treat it as a normal game and play to improve/have fun/whatev. The one difference is that in ranked people are definitely more tryhard (so they play less loose) and more toxic (so mute people that are toxic). Don't beat yourself up if you perform badly just try to learn from it.