(your) heart sinks

you become discouraged or disappointed.

My heart sank when I opened the letter and realized I had not been accepted into graduate school.

• heart is in mouth
• heart is in their boots
• heart is in their mouth
• heart is in the right place
• heart isn't in
• heart isn't in it
• heart isn't in something
• heart misses a beat
• heart of gold
• heart of stone
• heart out
• heart rules the head
• hearts and minds of
• hearts and minds of someone
• heart sinks
• heart skips a beat
• heart-to-heart
• hear yourself think
• Heath Robinson
• heat is on
• heat up
• heat up something
• heaven forbid
• Heaven help
• Heaven help someone