Hang in there, I know EXACTLY how you feel. I don't have a yorkie, but my puppy is about the same size- (currently 3.8 lbs at 4 1/2 mo). She is a shih tzu/toy poodle mix. During the 1st 2 weeks I cried a lot and was sure that I couldn't keep her. I had no idea how much she would change my life and I wasn't sure I could handle it. Luckily my boyfriend was not stressed like I was and assured me we could do it. Kaya is now almost 100% pad trained with peeing and getting better all the time with pooping. We have her in training class and she is doing very well. I am thankful now that I didn't rehome her as I am sure I would have regretted it. I understand how you are feeling, just hang in there, I promise it will get better!