Having weighed the pros and cons, I thought you ought to be conscious of the fact that you're working too hard.

weighed 是动词 weigh 的过去分词形式。weigh 本意是"称重"，引申为"权衡、考虑"。 weigh the pros and cons 是一个固定短语，意思是"权衡利弊"，其中 pros 指"优点、好处"，cons 指"缺点、坏处"。