Thanks for writing to H.C.M.for your query.
I have gone through your query regarding fever
going up and down for last three days, you are being told by your doctor as, suffering from tonsillitis
. At present you are given penicillin but still you have tempreature.
Considering your complaints and co-relating possibilities of pathological conditions you may be investigated for oter conditions of fever also. So you should go for-
(a) Widal test
(b) Blood for malaria
(c) Blood- CBC, ESR, SGPT, SSerum bilirubin
(d) Urine - Routine & Microscopic.
Though you are getting some responce to penicillin as you said that on monday your tempreature is not so high as was on friday, so you may wait for two days more , than after go ahead as advice above.