Since when are you hearing this?
The sounds that you suggest as pulse or blood flow is called tinnitus in medical texts.
Check this link for further readings
Following causes can be attributed for causing tinnitus
A sudden loud noise such as an explosion
Prolonged exposure to loud music
Hearing loss (20 per cent of cases: chronic noise damage )Head injury
Drugs: aspirin overdose, loop diuretics, aminoglycosides, quinine, welbutrin
Tinnitus can also be exacerbated by severe emotional or physical stress and brought on by loud noises (especially when heard in an otherwise quiet environment) and by physical damage occurring to the ear drum, cochlea or nerve.
You should get an Ent consultations along with examination of ear with an otoscope
Although this can be a sign of tinnitus as stated by Dr. Amitmunjal. This can also occur due to a rise in your blood pressure as well. (if you know your blood pressure is not the cause)
Then you can get some lipo-flavonoid which is known to help with this. This is a nutritional support to improve circulation in the inner ear. I have known of people who have taken this and it has helped them. But I would also be checked out by your doctor as well.
Hope this helps, If you need anything else please feel free to ask. If you found this helpful don’t forget to click the *
The more accurate medical description of this condition is Pulsatile tinnitus
I would like you to go through this link