Help with bad behaviour and teething

My puppy is about 3 months old and he is a pocket bully, xl bully mixed with some small breed I cant remember what one. Me and my boyfriend have been looking after him together as we live together but whenever my boyfriend leaves he starts acting so bad. He non stops barks and bites me hard. I try playing with him, taking him outside or doing training but he’d rather go biting furniture or me. I don’t know what to do as my boyfriend is starting work soon and I’m gonna be stuck with it. I discipline him but he barely listens to me like he does my boyfriend, how can I best discipline him? And what are the best things for his teething? He has teething toys but I don’t know what else I could give him. We can’t walk him until Friday after his jabs so I just feel really stuck at the moment especially when I’m alone with him.