Urge of vomiting. Stomach infection?

For past few weeks, during/immediately after eating food I feel like puking. I am sure this is not related to type of food as I get this urge during any meal. This is not happening everyday. Sometimes maybe once in a day or sometimes once in a week. It gets so tough sometimes that I fear I will puke right during meal. But at the same time I have never puked. I mentally try to overcome and have been successful so far. I have no idea why this is happening. Is this physiological or due to some stomach infection? On a personal level I don't feel this is too big issue but this has been hapenning for many months and now the urge is more than ever before. I am average built male, age 32, with weight 75kg and have preferred healthy food throught my life. Thanks for your advise in advance.