怪我太年轻是人是狗没分清
[guài wŏ tài nián qīng shì rén shì gŏu méi fēn qīng]
The user suggests regretting a past action, where they misjudged someone's intentions or character due to their immaturity or lack of life experience ('treating a dog as a person' means treating someone who does not deserve trust). This is often used in contexts of feeling cheated or betrayed.