Headache صداع

Whoever sees in a dream that he has a headache should repent, give charity, do good, or turn back from the sin he is committing, because of His saying, the Exalted:

وَأَتِمُّوا۟ ٱلْحَجَّ وَٱلْعُمْرَةَ لِلَّهِ ۚ فَإِنْ أُحْصِرْتُمْ فَمَا ٱسْتَيْسَرَ مِنَ ٱلْهَدْىِ ۖ وَلَا تَحْلِقُوا۟ رُءُوسَكُمْ حَتَّىٰ يَبْلُغَ ٱلْهَدْىُ مَحِلَّهُۥ ۚ فَمَن كَانَ مِنكُم مَّرِيضًا أَوْ بِهِۦٓ أَذًى مِّن رَّأْسِهِۦ فَفِدْيَةٌ مِّن صِيَامٍ أَوْ صَدَقَةٍ أَوْ نُسُكٍ ۚ فَإِذَآ أَمِنتُمْ فَمَن تَمَتَّعَ بِٱلْعُمْرَةِ إِلَى ٱلْحَجِّ فَمَا ٱسْتَيْسَرَ مِنَ ٱلْهَدْىِ ۚ فَمَن لَّمْ يَجِدْ فَصِيَامُ ثَلَـٰثَةِ أَيَّامٍ فِى ٱلْحَجِّ وَسَبْعَةٍ إِذَا رَجَعْتُمْ ۗ تِلْكَ عَشَرَةٌ كَامِلَةٌ ۗ ذَٰلِكَ لِمَن لَّمْ يَكُنْ أَهْلُهُۥ حَاضِرِى ٱلْمَسْجِدِ ٱلْحَرَامِ ۚ وَٱتَّقُوا۟ ٱللَّهَ وَٱعْلَمُوٓا۟ أَنَّ ٱللَّهَ شَدِيدُ ٱلْعِقَابِ

“And complete the ḥajj and ʿumrah for Allāh. But if you are prevented, then [offer] what can be obtained with ease of sacrificial animals. And do not shave your heads until the sacrificial animal has reached its place of slaughter. And whoever among you is ill or has an ailment of the head [making shaving necessary must offer] a ransom of fasting [three days] or charity or sacrifice. And when you are secure, then whoever performs ʿumrah [during the ḥajj months] followed by ḥajj [offers] what can be obtained with ease of sacrificial animals. And whoever cannot find [or afford such an animal] - then a fast of three days during ḥajj and of seven when you have returned [home]. Those are ten complete [days]. This is for those whose family is not in the area of al-Masjid al-Ḥarām. And fear Allāh and know that Allāh is severe in penalty.”

Quran 2:196 · Saheeh International

A headache is trouble from the one the head stands for, namely his chief [ra'is]; the interpretation of headache basically refers back to the chief. It is said that it is a sin from which one must repent.