My 13 months (7 month born)old baby had fever starting Saturday.Till Wed morning his fever was continuously increasing and decreasing. By yesterday afternoon his temperature became normal and he was playing. but by evening he started crying continuously without any reason.he was crying the whole night and it's the same today also.He had UTI in the past so this time we checked his urine test it was normal.Initially he was on Para V and extacef drops. yesterday doctor changed his medicine to azithral.Also for the past few weeks he is continuously shaking his head back and forth.His current weight is 7.26 and birth weight was 1.16.What should be the ideal weight at this stage.Also what might be the reason of his crying.He is not eating or drinking properly.