Hungry even after eating. not lactose intolerant. any lead what could be wrong?

Unsure: The most obvious concern would be not fatting enough calories for amount of physical exertion. I recommend a full assessment where your weight and other factors specific to you can be taken into account.

Diabetes?: Diabetes can have this in some people. There could be other reasons. You should see your doctor and talk to them about this.

Do a diet diary: It would be helpful for you to do a diet diary of everything that you consume, include amounts, preparation, frequency, even gum and mints. Take that to a dietitian and have a consult. Make the diary include an entire week and weekend.

Tummy not satisfied: Seemingly you are having god appetite and eating well. Anyhow, if you normally eat large amount of food and now not, your tummy is not full/satisfied and wants more food. If you are not gaining wt and constantly eating more than usual, check with doc as you may have high-functioning thyroid. Some medicines can make you feel hungry all the time too. So, consult doc. Good luck.

Always hungry: See your doctor and have him rule out the possibility of celiac disease. Good luck.