I have a 1.5 year old cat that will be sitting quietly on a stool, chair etc, and then he will, apparently at random, react to his tail movements and run away and sprint around the house. There seems to be no reason for him to react this way and it often results in him becoming increasingly aggressive towards the other cat (who is 8 months old). He behaved this way before the other cat came into the house, too.
When he is in this state he reacts aggressively towards any interaction.
While he is an indoor cat, he spends most of the early mornings chasing and playing with our other cat. Also I take time to play with him via laser-pointer when I get freetime
Is this normal for a young cat or is it something I should be concerned about?