Usually, my neck starts to hurt and my blood pressure drops.
Neck pain along with a drop in BP can be due to muscle strain, poor posture, dehydration, or sudden position changes causing temporary low blood pressure. Try to stay well hydrated, avoid sudden standing, maintain good posture (especially while using phone or computer), and do gentle neck stretches. Check your BP regularly and take your medicines as prescribed. If the pain is severe, frequent, or you feel dizziness, fainting, or weakness, consult your doctor to rule out nerve or circulation problems.