1. "我没事" 理解为最近没做什么新鲜事儿.

Nothing new, it's just hot like hell recently.

Same old, it's just too hot recently.

2 "我没事" 理解为我身体情绪什么的挺好的,

I am fine/OK, but the high temperature has been killing me recently.

后半句随便换吧,都行.