There is no reason to worry about... If you take it for a period of time and you feel pretty good means that your body feels perfect and you do not get too much stamina.

i think the best advice for you will be to make time for eating healthy. You probably know that everyone looking to be healthy need to have 4-5 meals per day. As you said, you absolutly do not respect this regim. And this is not good. Be aware of the consquences you risque!

Do not forget to carry with you some fruits. This is the right source for vitamins. You get a lot of useful advices here, so keep its in mind.