Is my mom right about my boyfriend?

I'm 22 and my bf is as well and I've been dating him for 2 years now. He is very good to me and loves me very much and I truly believe he's not like most guys because he ALWAYS listens to me and if he sees that I don't approve of something he's done or said, he changes it immediately. It's almost as though he looks up to me and he's always saying if I have a problem with something he's doing, he changes or stops it straight away because he trusts my judgement and believes in my intelligence, he's also told me that he admires me. He works hard at keeping our relationship running smoothly and i believe, with out a doubt in my mind, that he respects me and loves me. he also helps out a lot around my house whenever he comes to visit me because my mom is divorced and my older brother is very unreliable. He cuts down trees, rakes the lawn, helps me with my pets plus much more and he's always there for me when i need him. Btw, I stay at my house alone with my bro in FL and I only see mom on weekends b/c she works in NY, so having my bf around to help is very convenient for me. We have lots of pets and my bf has helped me take them to the vet and he's also gotten us discounts with the vet b/c he knows her son. Anyway, last night, he and i were going for ice cream and i asked my mom if she wanted one and she reluctantly said yes (she's on a diet) and as my bf and i were getting ready to walk out the door, my mom hops on our treadmill jokingly and says she's gonna start working out now until we get back with the ice cream, because she needs a head start, then my bf (stupidly) but jokingly says while snickering, "uh-oh, well we're not getting back till' 12 so you're gonna be on there a while!" The time was 10:30 and he was joking because when i confronted him about this today, he said he was really trying to make her laugh because it wasn't even possible for us to get back that late since Dairy Queen is only 5 mins from my house. My mom is very big on youngsters respecting adults and shrewd jokes are not okay with her and she told me she believes my bf is "pushy," "rude," and "disrespectful" for making jokes like that and she told me she doesn't like him for me and i need to explore my options. My bf tries too hard to be funny (he's not the best at jokes) and sometimes he comes off weird or obnoxious from the jokes he tells that are of the same nature as the one he made to my mom. He's also done that once before when he sat down at my kitchen table to eat and across from him, my mom was on a ladder in the other room putting up curtains and he said,"Well, hey! I'm getting dinner and a show!" My mom took it offensively and pulled me aside when i was alone and told me she thought he was rooting for her to fall or something, thinking that would be the "show" he was joking about. I also confronted him about that one and he said that was not at all what he intended b/c that's a serious thing and who would root for someone to get hurt? I didn't quite get her being mad at that joke either b/c i know he'd nvr joke abt someone getting harmed much less my mother. So is mom right about him? I'm sorry this came to be so long, i just wanted to explain thoroughly.