Hi! I give my 3 year old daughter with autism 3mg of melatonin each night. Tonight about 20 mins after taking it she started shaking- like the chills- not like a seizure, and looking like she was about to throw up. It lasted 5-10 mins and then she seemed alright. This has also happened once before. Should I be concerned? Also, every evening after she has taken it she has a cough off and on for about an hour. Should we decrease her dosage or stop giving it to her? Thanks!