Issues with my sex life

Don't get me wrong when I say this..my boyfriend isn't awful in bed, but he just doesn't last long and once he cums he's done. He does things to make me not confident in my own body, so I barely ever want to have sex with him for that reason (yes, I have talked to him about it before). But also he always does a weird laugh when he has finished, and in the beginning I thought it was kind of cute, but now it's just anoyying. We spend all of our time together so I never really get a chance to rub one out unless I'm in the shower, but lately I have just been yearning for something more. I don't know if we need to spice things up and try something different, or if this is us fizzling out? My ex boyfriend was really good in bed and had a big cock..so I feel like I know what I'm missing out on and it just makes me hornier thinking about it.