Sudden Pulsatile Tinnitus After Lying Down in Bed

Pulsatile tinnitus started in my right ear after lying in bed for 15 minutes. It is a thudding sound; in a morse code dots only pattern, so it's constantly dot, dot, dot, dot.

I started taking a new medication that can affect blood vessels the day before. I only took one.

But I'm wondering if culprit is the medication as the pulsatile tinnitus is only in my right ear, and only when I'm lying on my left side or my back. It goes away completely if I lie on the ear with the pulsatile tinnitus, so I'm wondering if it has something to do with muscles.

 

Probably nothing to worry about. What type of medication is it?