Thanks for your question regarding your girl Lenni who seems to be quite stressed and highly strung. It isn't unusual for cats to be this skittish when in a new environment. It sounds like Lenni is just getting used to her home now which is great, and a few environmental modifications can make things so much less stressful for her. The litter tray was a great idea, and make sure this is in a nice quiet, low traffic area of the house for her. I would also suggest the feline pheromone diffuser here - Feliway, as this will hopefully help ease her anxiety in this new home even more. A diffuser or two in your home would do the trick nicely and you can get this from your local vet clinic. You can read more online about this here: www.feliway.co.uk . You also need to get the layout of your home right, so that Lenni doesn't have a clear line of sight to the neighbourhood cats, and so that she has somewhere to get away and hide (a safe space). There is an excellent article that covers the needs of cats in the home, and this will really help you: http://journals.sagepub.com/doi/pdf/10.1177/1098612X13477537
So - in terms of getting a puppy, I do think you can make this work. It will be a lot easier for everyone, introducing a puppy compared to an adult dog, and this will hopefully give Lenni some time to build up confidence as the puppy gets bigger. I would recommend confining the puppy to one room for a start, and letting Lenni have free roam of the house for a couple of weeks. This will allow Lenni to get used to the smell, sight and sounds of the puppy and get used to him or her. The feliway will also help in this situation. Never force Lenni to be in the same area as the puppy, and always ensure the puppy (or adult when he/she grows) doesn't have access to Lenni's safe place. As per the article, aim to have some high spots for Lenni to escape to.
So long as you meet Lenni's environmental needs, and introduce this puppy slowly, you should be ok. Assistance from Feliway will also be useful, and if behavioural issues do develop once the puppy is in the household, you can follow up with your local vet to discuss an anti anxiety medication like Clomicalm, although it is unlikely she will need this. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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