Apologies for the poorly worded post but I'm nervous and not thinking straight.

I'm supposed to be picking up a puppy tomorrow afternoon and I think I'm getting cold feet. I'm planning on talking to my therapist about an emotional support dog but I haven't spoken to her about it yet. I feel really confused!

I'm scared I will be too stressed and overwhelmed with having to take care of a puppy and also work as well. My boyfriend and I have been doing pretty good lately and I'm scared bringing another living being into the mix will be too stressful and then I won't have a good handle on my emotions anymore. I'm also scared about how much this limits our freedom (to go on camping trips, maybe even travelling, going out to restaurants, or even just visiting places where I can't bring the dog). I know I will get very little sleep in the beginning and I'm scared about how lack of sleep will affect my mental health and work productivity.

At the same time my family thinks it's a good idea for me to get a dog because I'm really lonely working from home and being alone for most of the day, it will help teach me more responsibility, and I will have a companion when my boyfriend and I are fighting. 

I live with my boyfriend and initially he wasn't on board (he suggested getting cats even though he's a dog person, I love cats too but prefer dogs as well) and I was able to change his mind. I think he is hopeful that me having a puppy will reduce my clinginess with him and I also said I would take on all the responsibility of a puppy and the financial aspect as well. I said this because I want the dog to see me as it's favourite person, and animals LOVE my boyfriend (and vice versa) so I feel like  I can't compete and if I want companionship while my boyfriend and I are fighting then I need to be it's favourite person so it will want to stay with me. 

I told my boyfriend that I'm scared I won't be a good mom to the puppy but he isn't worried about that and knows I will take care of it. But I'm scared about how stressed I'll be though because my mental health really declines when I'm stressed out. I'm scared about how it will affect my relationship with my boyfriend too since lately we've been pretty good. He thinks we've been good because I'm happy he said yes to me getting a puppy.

Anyway I've already given a $200 deposit to reserve the puppy and my boyfriend already told his whole family and I told mine as well. But I'm scared now and getting cold feet and I don't know if me getting a puppy is the self destructive impulsive thing or if me being scared of getting the puppy and considering backing out of it is me being impulsive or is it both? I don't know what to do and nobody wants to tell me what I should do because they think it should be my decision (since it's my puppy). I need guidance