Our yorkie puppy, Simba, is almost 3 month old and has been with us for two weeks. He's almost potty trained, he would sit by the door or ring the bell when he wants to go outside. However, we live in an apartment complex, we don't have fenced yard. So we take him out for potty on a leash every time. He sometimes goes right away, but he would still keep sniffing around, so we thought he might have more business to do. Instead, he always finds some leaves or other random stuff and get totally distracted and probably thinks it's play time outside. Now, he would ring the bell just to get out and play, not even potty

It's like four time in one hour...
How can I stop him from tricking us to take him out for play? Maybe I should pick him up as soon as he finishes his business?
Also a minor thing, Simba goes hyper couple times at night. We leave him in a four by four exercise pen with pee pads. He sometimes would cry for us around 3AM and being hyper for ten minutes. I usually pet him to calm down. Will he grow out of his mid-night hyperness?
Thanks!!!!!