16 month old not eating at all. Need help imm.

My son is 16 months old and very very fussy to eat . since yesterday he has had only milk and water and feeling very weak. I called his doctor and they say , its ok, he will eat when he’s hungry.

Last weekend he had indigestion problem as he was refusing to eat and crying all day and had hiccups while eating. I guess it was because of ghee in khichdi. (Very fragile stomach ) I gave him Nux vomica 30x. he’s still taking it 2 pills 4 times a day for 3 days now. He was better on second day and third day again he’s quit eating completely.

I am unable to allay my worries.
Here is the detailed information about ethan.

Breastfed until 13 months. Fussy eater since 6 months old. Was fussy even to breastfeed.

Very cheerful. Friendly with most kids. Off late, not sharing his toys. Loves people around. If he’s feeling better, plays by himself Very comfortable with strangers.

Never eats outside the house i.e restaurant or car. Eats only when he’s too busy with his toys. Very difficult to distract him as he remembers after the first morsel, that I am around only to feed him. I offer both veg and non veg food. On worst days he would eat nothing at all except sipping some water or juice.
When he’s hungry he clings to me and starts crying.

The moment he has some food or milk in his tummy he’s overexcited laughing and playing but that’s only for a short while until there’s a drop in energy and then cries and goes to sleep

Sleep: Never sleeps thru the night. I have to sleep with him. He goes to bed by 9.30 or 10p.m and I go to bed by 12 he would wake up several times and the moment he sees me hugs and sleeps. Sometimes sips milk. Uses glass. Never used a bottle. Light sleep. Day time nap .. just one for an hour and a half but that’s also not in a stretch if I am not with him. He would wake up to search for me.

he doesn’t like to be wrapped at all. He’s comfortable in cold weather. Sweats only on head , a little no odor.

Vaccinations:12 months and 15 months vaccines are still pending. Earliar shots he had fever. No change in health noted.

I have to force him to eat and even then eats very little quantity. Passes BM everyday.
No food allergies. Reached milestones on time. Started walking by 12 months old. Only says mamma, duck that’s rare.

Already has 14 teeth. Had frequent loose motions and vomiting since 8 months by 10 months it was so severe that he couldn’t live without antibiotics. Once he skips ondem –antibiotic, he would start vomiting. Loosemotions would follow. Very low immune system at 1o months started homeopathy. That took care of his loose motions and vomiting but not his appetite. He was always at the homeopathy doc’s clinic every 10 days for upset stomach or no appetite or cold and cough. But the doc gave always give pellets mixing 4-5 medicines. He also is not taking my son’s problem of no appetite seriously.

Grinds teeth occasionally. Healthy skin. Injuries heal fast. Nails have white spots on. Normal palms. Built lean and thin. no coating in tounge sometimes little whitish coating . he has the habit of keeping his tongue out most of the times. No he has no fears of dark

Birth weight 8lbs 2ozs. Had PUPPS during pregnancy since 34th week delivery- c-section. My son has a negative bloodgroup A-VE. Breastfed for 13 months.