Why would I feel angry with no apparent reason ?

I think that there are many reasons why you would feel angry with no obvious reason. Hormones can play a factor, scientifically. We can feel out of balance, per say, but this is normal in a sense. Another reason could be because of this pandemic. Since we are quarantined inside, we aren't outside breathing fresh air, getting exercise, or even getting any sun. It's normal to feel out of balance with your emotions, especially with the emotion anger. Don't feel like there is anything wrong with you because this is normal! Using outlets such as drawing, exercising, listening to music, etc. can help you feel better and feel less stressed and angry.

It could be due to suppressed emotions which are pent up from past events- this could be events you have blocked out from your brain in order to protect yourself. I often have the same issue and think it could have stemmed from my childhood. Or it could be just due to having a mental illness and the build up of anxiety and anger can not always be explained as so simply to a particular event or memory. If you talk to a therapist or counsellor, they will be able to help you solve and work out why you may be feeling this way currently.