I Had The Flu Last Week. This Morning I Awoke

I had the flu last week. This morning I awoke and my left ear felt like it does when I'm in an airplane - sound is dull and muffled. As the day wore on, I noticed sound had recovered in the left ear, but it was like there was a tiny echo. Also, music sounds out of pitch in that ear. This has never happened to me after a bout of flu.