my puppy is acting very aggressive
 

our little morkie has become extrmeely aggressive all of a sudden. he was always pretty good and listened and has been living and playing with my roommates puppy for the past 5months. all of a sudden on saturday night when he was in the room by himself becaus ewe were having dinner hes seemd to have been more aggressive when we let him out. He even started attacking us when we tell him to start barking. The thing that really alarmed us is that he started playing extmreelly rough with my roommates dog now and attacking her. overall he just all of a sudden listen as much anymore and he randomly attacks us and the other dog now which he used to never do.

Some events that followed up to this is that he got neutered 2 weeks ago and my bf came to visit me for a week. we thougth he was being crazy because of his surgery but even right after the surgery he was fine and idnt show any aggression its only after 2 weeks of it when everything healed. we also thought it might be because my puppy is jsut jealous that my bf came back even though he took care of him before he left.

what the heck is going on with our little pup why is he so aggressive all of a suddena nd atacking all of us now?

p.s. he just lifted his leg and peed on me intentionally! he has NEVER done this before!!