Your body mass index is below the normal range. First ,the most important and one the essential components of normal life is proper sleep so that our body and mind can get adequate rest. With your case history ,i would suggest moderate exercise in the evening and yoga classes in the morning for your biological clock ( medically called cicardian rhythm )to get on track.I think the role of medication in your case is limited. FOR you gain weight ,proper food mainly with rich fibre content and heavy breakfast around 7: 30 am would do wonders not only to your weight problem but also to your acidity complaint.Remeber to take the rest of your food on time and have meat if you are non veg in the afternoon. And always better to add nuts like cashewnut,groundnut which has high calorific value, which will surely enhance your weight in a proper manner. With your case history, i am sure that with right attitude and determination ,you can overcome your medical problems which has a more psychological component than pure medical.. For acidity ,i would suggest you take medication like RANTAC 150 MG twice daily TILL you are well & for your feet burning you can continue taking multivitamins.