A head cold with possibility of blocked eustation tube and infection in the ears.
Get checked out by the doctor to make sure you do not have a bacterial infection.
For help at home, do steam inhalations. Get a bowl of hot water with vick or olbas oil and inhale the steam with yur head covered with a towel. Make sure yu do not get scalded. This will help to loosen up the congestion.
The crackling and popping that you hear is the mucus inside.
Drink plenty of warm fluids. Avoid milk products for the present as that encourages the production of mucus.
Wishing you a speedy recovery.
Sounds like you have a head cold to me. Did this all come on suddenly together? You should probably go to the doctor to see if you need an antibiotic
And I feel cracking or popping in my head??