微笑勉强的有点心疼眼泪滑落的有点失控
[wēi xiào miăn qiáng de yŏu diăn xīn téng yăn lèi huá luò de yŏu diăn shī kòng]
This conveys the bittersweet feeling where smiling through pain only makes it harder. Despite trying to remain strong by forcing a smile, one ends up shedding uncontrollable tears due to deep sorrow or distress.