Thanks for the query to H.C.M. Forum.
In my opinion these symptoms may be due to .
1 Hyper acidity or gastritis
, as you stated that pain in stomach, lightheaded , nausea and slight discomfort.All these symptoms are an indication of acid reflex in stomach .Upper G I endoscopy
will confirm the diagnosis.Avoid greasy , spicy , junk foods. It might also help avoid drinking or eating for 2 hours before you lie down.
2 Food allergy
may be the next reason . When some type of food ingested it develops allergy and patient feel such type of symptoms.
3 Overeating may be the next reason. Sometimes excessive food develops nausea and vomiting
In my opinion if such symptoms develops , take some type of antacid but if symptoms are severe , you may need drugs like proton pump
If symptoms reoccurs then consult a physician .
Good luck. Dr. HET