From the picture provided, this appears to be "cobblestone" throat. Cobblestone throat refers to the lumps/bumps at the back of your throat.
They usually appear as a result of repeated irritation of the back of the throat from mucous from the nose or from acid reflux from the stomach. It is a common condition seen in patients with postnasal drip from sensitive nose (Rhinitis) or sinus infection (Sinusitis) as well as acid reflux from the stomach (Laryngopharyngeal reflux).
A nasoendoscopy may be recommended to assess your nasal cavity, drainage pathway of your sinuses and the area around the voice box region to determine the likely cause of your cobblestone throat.
Hope this helps and all the best.