Trouble with Introducing a new cat. Please help!?

[ninababy101108]

I have had my cat since she was a kitten.*Haley* She is about a year old, and never experienced other cats before. I adopted another cat, a male*Merlin*, about the same age as my other. I tried to sneak him in, but Haley got in behind me and freaked out. She's been hissing and growling like crazy at him. I moved him into a safe room as soon as possible.

She is very angry with me and my boyfriend. She hisses more at me than at Merlin! I can't even approach her without her throwing a fit. I had to put her up last night because she was acting so horribly, and she continued to growl and hiss all night. I used a spray bottle on her, when she tried to attack me. She's always been a little feisty, but never this bad.

I rubbed a few towels on my other cat and stuck them around the house. I don't let them see each other, and I try to make both as comfortable as possible. I gave Haley treats when she was acting nice to me, but that changed in a matter of minutes.

I don't know what to do! How long does this last? Will she ever get along with Merlin? I need some advice on how to gain my cats trust back, and how to react to her hissing. It scares me!
Thanks!

They are both spayed/neutered.

 

[Ruben Delatorre]

I had that too.... i basicly let them get along on there own they hissed growed like fuaght a lil like scracth but not bad but then like it took about 1 week or a week and a half i did this twice cuz i had one cat then got another then another yea so just let them be and theyll get along