I am a professional singer who in the past year has had maybe 3 occasions where, while at a gig, I would lose part of my voice....lose a note or two in my range all of a sudden..where I would sing fine until getting to the lost note and then only air or a squeak would come out. No pain but tightness in my throat, felt like a frog in the throat you can t clear...would go away within 5 -15 minutes. Have been singing for over 20 years and never had this problem before. ? Muscle tension dysphonia?