You may be under more stress than you realized. For reasons not entirely understood, in general, girls tend to get sad and boys tend to get mad when they are over-stressed. Please take a look at your lifestyle choices and your level of stress.
If you are not getting at least 8 hours of sleep a night, that’s a place to start. Many guys your age are into gaming that keeps them up at night. You didn’t share whether that is the case with you, I know. I’m just suggesting that if you aren’t getting enough sleep, the problem may be as simple as that. At your age, your brain needs restorative sleep to function normally. Your hair-trigger temper may be coming from sleep deprivation.
Another source of irritability is lack of enough active exercise. If you aren’t getting in 30 minutes or more a day, your body doesn’t have a way to discharge energy. I hope you are involved with a sport or at least going for a run before or after school.
Finally: How’s your diet? Are you giving your brain and body the nutrition you need to be at your best. Make sure you eat a healthy breakfast. Get a good lunch at school. Avoid junk food and caffeine and you’ll probably feel better.
Those are only a few reminders. Taking care of your physical health is key to being mentally healthy.
As for the stress: You seem to be doing well in school. Good for you. But doing well without too much stress means doing school work in a routine and regular way. If you put things off until the last minute; if you are pulling all nighters to get things done; or if you are trying to do the work when you are run down, it’s a prescription for stress.
I suspect you do know what to do so just do it if you aren’t already. Set a reasonable schedule for study time and make sure you don’t leave things until the last minute. This is especially important if you are thinking about college. You need to establish the habits of self-discipline around studies now so you will take those skills with you.
I wish you well.