They haven't been together very long. I think you are doing very well since the introductions were rather immediate. The normal course is to keep the newcomer separated for a few days and give both a chance to adjust to the new scents.
I would suggest spending some play time with your girl by herself. This will help her feel more secure and she will start purring again.
As to the growling, unless there is blood drawn, don't worry about it. Most of the time, cats are good at working out some sort of truce. There is a lot of noise but no action.
I would suggest spending some play time with your girl by herself. This will help her feel more secure and she will start purring again.
As to the growling, unless there is blood drawn, don't worry about it. Most of the time, cats are good at working out some sort of truce. There is a lot of noise but no action.