Blood in stool. What to do?

My 4 months old son gets sick around 15 days ago when he was not completed his 4 months having loose stools, vomiting and fever then I take him to general physician he treated him with some liquid medicine for 2 days but it didn't work for him so I take him to child specialist he told me that condition is not very well it will take around 4-5 days to recover and if u feel u can take him to children hospital in case u see anything serious then I take him to hospital they admitted him for few hours and gave him some drip and discharged him in morning but no. Of stools didn't comes down as soon as he feed it comes out through loose stool I stick to medicine given by child specialist prior to hospital and after that I m giving him homeopathic medicine calcerea phosphorus for teething and after 2-3 days no of stool comes to 1-2 per day but from yesterday onwards there is a little red color visible in his stool and no of stools also rises to 5-6 a day I think it's blood. What to do?help