Hi, constant headache, difficulty in concentration, forgetfulness, feeling stressed up, negative thoughts about future and irritability are the common symptoms of depression at your age. There may be underlying anxiety also. If those symptoms persist for more than 2 weeks you have to think seriously.
Next Steps
You should communicate this problems with your parents or near and dear ones.
Health Tips
Keep yourself busy in works whatever you like. Mix with friends physically. Avoid social media. Do physical exercise, yoga, breathing or relaxation therapy. These will decrease your stress a lot. Even if your symptoms persists for more than 2 weeks consult a neuropsychiatrist at the earliest. Thanks.