Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain it seems that the symptoms of its turns yellow turning of nail and breakage from right side of the nail with bad smell and history of some pain and redness in the side skin of nail also occurs commonly due to causes like bacterial or fungal infection.. This condition is known as PARONYCHIA.. It can occur due to conditions like traumatic injury to the side of the nail like while washing clothes or dishwashing, injury while cutting nail, nail biting habit etc, overzealous manicure etc.. I would therefore suggest you to consult a General Surgeon and get evaluated and a thorough clinical evaluation is generally sufficient for diagnosis.. You can be advised to apply a combination of steroid, antibiotic and antifungal ointment over it.. If it is painful topical application of numbing ointment and taking anti inflammatory painkiller like Ibuprofen can help.. Do cool compresses over it.. For better growth of nails take multivitamin supplements.. Massage the nails with olive oil or vitamin E gel.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.