Talk to Gastroenterologist on Severe Diarrhea

My one-year-and-eleven-month-old son has been suffering from diarrhea for eight days. On the first day, he had a fever and had 10 episodes of loose motions. I administered 'cefspan (cefixim)' for six days and gave him 'panadol' for the fever. The next day, his fever subsided, and his bowel movements improved, but after two days, he fell sick again, experiencing loose motions eight times a day. I'm very concerned and unsure about what to do. I've been giving him fluids to prevent dehydration.