Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concern.. As per your complain small white bumps at the back of tongue can be in Circumvallete Papillae and it can occur due to common conditions like eating something very hot or in case of throat infection, Oral infections or allergic reaction.. Nothing to worry as it is not a serious condition and will resolve gradually on its own.. You can do warm saline gargles and take anti-inflammatory painkillers like Ibuprofen.. The piece of flesh that you have observed under the tongue out most probably Plica Fimbriata which is a fold of mucosa and is a normal structure and not any pathology.. Hope this information helps..