Hi.. Thanks for the query.. As per your complain bleeding from tongue after brushing it gently with a toothbrush and also having the symptoms of soreness or pain on the sides of the tongue seems to be most probably due to inflammation of the tongue known as Glossitis and is caused due to common causes like Vitamin B 12 deficiency, trauam to the tongue with sharp teeth, eating exces of sour or tart foods, dry mouth etc.. As you are having inflammation of the tongue it is causing difficulty in eating salt and acidic foods due to it becoming more sensitive.. I would suggest you to consult an Oral Physician and get evaluated and a thorough clinical evaluation and investigations like serum Vitamin B12 levels, Hb% etc can help in diagnosis... As of now start taking Vitamin Bcomplex supplements... Take anti-inflammatory painkiller like Ibuprofen.. Avoid spiacy and sour foods.. Do cool water rinses and suck ice.. Drink plenty of water.. Hope this helps.. Thanks and regards.