If you’re doing it just to TEST him, then yes…it will probably annoy him. He HAS power, by spades and you’d be wise to respect and acknowledge that power even if you have yet to experience it yourself. He might not even bother with your request.
If you want him to GUIDE you…that’s a different story, and probably the letter you should have written…and STILL CAN.
As for your offering, I don’t know. I have my own home, my own temple space, alter space and area just for where I place offerings since I have frequent contact. I would recommend that you try to find yourself a suitcase maybe, and make a portable temple you can place under your bed. You could place the offering in it beside your bed or something.