New kitten - old kitten hissing at everyone

Introduced a new kitten to my other two cats. Probably too suddenly after what I have read now. The kitten was freed to roam the house shortly after it arrived. My other male 2 year old cat is not responding to it very well. He's normally dominant but generally frightened of noises and people. When it's just me and my fiance he thinks he's the boss. Now he's just been hiding the whole time since the kitten has been around for two days. When ever the other kitten is in the room he just hisses and spits then run away.. Even when the kitten is not around he keeps hissing me and my fiance. He keeps meowing and wants a pat but hisses at the same time he's so confused. Is it normal for a male cat to hiss at their owners when a new kitten is introduced? I just want him to be comfortable again and back to his normal self. I've been locking the new kitten away at night.

Hi ryannnnnnnn and welcome to TCS!

All sorts of things can happen when you introduce cats and I would say this is your boy's way of dealing with it.

It is not to late to go through the whole introduction process - it can be done at any time and it is definitely worth it.

Here's an article describing the steps to take.  And please to feel free to ask more questions!