The cause(s) of the multiple issue can only be know by a doctor,after examination. So your boy should be seen by a doctor.

Always check body temperature with a thermometer

Teething does not make children ill. It is a normal physiological process. Most babies start cutting their first teeth around 6 - 11 months which coincide with period when exclusive breastfeeding is stopped and complementary feeding is started so there is reduction in the protective factors against ill-health received via breast-milk. This period of 6 - 11 months is also the period that babies begin to also explore the environment more making them to come in contact with germs.

Loss of appetite and not playing may be the first symptom of sickness…...
So if it persists kindly see a doctor preferably a Paediatrician for thorough evaluation and treatment.

Loss of appetite and not playing may be the first symptom of sickness…...
So if it persists kindly see a doctor preferably a Paediatrician for thorough evaluation and treatment

Hope you take the malaria drugs with paracetamol?