Girl on Top

Me and my boyfriend always have really amazing sex, but when I'm on top I always feel it gets a bit lame! Our sex is always really rough and fast but when I get on top it just loses its tempo 
Like I know what to do, I move up and down and stuff but it just seems a bit flat compared to when he's doing his thing? 
Any tips advice etc all massively appreciated - I really wanna get amazing on top!! Any sex tips at all welcome xxx