It just doesn't seem to matter how I long I walk him...he won't go. Not to be too graphic, but I can see the evidence peeking out

I have only had him since Friday, and in that time he has pooped only 4 times (twice outside and two times inside). I can tell that he doesn't want to go inside that he tries really hard to let me know. I have kept him out for about 30 minutes at time to get him to use the bathroom, and he just won't go. Once he started to go, and I started to praise him, and it bothered his concentration I guess, because he got up and walked off, and never did poo.
He doesn't seem to really know what puppy pads are for. I bought some of them just in case, but he isn't the least bit interested in them, and I actually don't want to get him started on them since he hasn't used them before due to fact I have a toddler (who likes to put things in his mouth

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