Hello Welcome to healthcare magic. I have read your question completely and understand your concerns. Acid taste in mouth, pain in sternum area, heart burn, lump in throat feeling could be due to GERD, where the stomach acids go upwards into the food pipe cause inflammation of the food pipe. You could take either Lansoprazole 30 mg once a day or Rabeprazole 20 mg once a day for 4 weeks and see if your symptoms settle down. Take this tablet on an empty tummy preferably in the morning. If after a month, your symptoms still do not settle, then see your doctor. GERD can also cause early satiety, that means you feel full faster. This may prevent you from eating a healthy diet leading to nutritional deficiencies like anemia and multivitamin deficiencies. This can lead to tiredness and fatigue. This can also cause numbness in hands and feet as there could be Vitamin B 12 deficiency. Cold hands and feet along with tiredness can also be due to hypothyroidism or it could be due to a circulatory problem. May I advise you to get some basic blood tests done - complete blood picture / full blood count to check for Haemoglobin, serum creatinine, blood glucose and Thyroid function tests. These are to find out the cause for your tiredness and cold fee and hands. kindly consult your doctor with the results and to get a full evaluation. You could also take a multivitamin supplement with at least 500 -1500 micrograms of Vitamin B 12. That may help your numbness symptoms. I hope this answer has helped you. Thank you. Regards Dr Sunita Sayammagaru