Thanks for writing your query.
Your symptom of dizziness
appears to be due to cervical spondylosis
This can occur due to improper position of neck while working on computers for long periods or reading while lying in bed.
If you have to work on computers for long periods, you should take care that your neck should not be too much bending forward. Same precaution you should follow while reading.
You can take Betahistine
16 mg 2-3 times a day for relief from your symptoms.
If pain in neck is also present, you can take pain killer like Ibuprofen
one tablet twice a day after meals along with a muscle relaxant
Also get yourself examined and investigated by an Orthopedician.
If the symptoms persists, get a MRI of your head and neck done.
I hope this is helpful to you.