Can eating unhealthy (junk food) every day cause vomiting, dizziness, tiredness and headaches? is this my body warning me?

Junk food: has a lot of additives, preservatives, transfats, and sugar in the various products. Thus, you can get symptoms such as GI distress, fluctuating blood sugar, etc. Talk to your doctor about shifting to a low carb and higher protein diet so you will have energy from good fat rather than from sugar. Your cravings will gradually diminish. Peace and good health.