Is it ok to raise my voice to my parents in a respectful way, just out of being upset? My parents do not find it disrespectful and don’t mind it when I do that.
Raising the voice is a universal sign of disrespect.
Allah (ﷻ) said:
يا أيها الذين آمنوا لا ترفعوا أصواتكم فوق صوت النبي ولا تجهروا له بالقول كجهر بعضكم لبعض أن تحبط أعمالكم وأنتم لا تشعرون
O you who have believed, do not raise your voices above the voice of the Prophet or be loud to him in speech like the loudness of some of you to others, lest your deeds become worthless while you perceive not - Qur'an 49:2.
No one does it when they are expressing love, happiness or gratitude. It is usually when you are angry and upset, which is true in your case as you admitted (@"out of being upset"). It would not have been respectful if done to the Prophet (ﷺ) nor is it respectful when done to your parents.
When a person is upset/angry, they should real respect by keeping themselves calm, composed and still treating their parents with nothing but the best words and gentlest tone.
وقضى ربك ألا تعبدوا إلا إياه وبالوالدين إحسانا إما يبلغن عندك الكبر أحدهما أو كلاهما فلا تقل لهما أفّ ولا تنهرهما وقل لهما قولا كريما
And your Lord has decreed that you not worship except Him, and to parents, good treatment. Whether one or both of them reach old age [while] with you, say not to them [so much as], "uff," and do not repel them but speak to them a noble word - Qur'an 17:23.
Don't raise your voice!