I did up my belt too tight which left marks on my skin and irritated it.
My belt was too tight and it made my skin itchy.
1) I did up my belt too tight which left marks on my skin and irritated it.
「ベルトをきつく締めすぎて皮膚に跡ができヒリヒリした。」
「ベルトをきつく締める」は do up one's belt tight
irritate で「炎症を起こす・ヒリヒリさせる」
2) My belt was too tight and it made my skin itchy.
「ベルトがきつすぎて皮膚が痒くなった。」
My belt was too tight で「ベルトがきつすぎる」とも言えます。
made my skin itchy で「皮膚が痒くなった」
ご参考になれば幸いです！
日本 
