Some advice needed

So my SO is 40 I'm 23 and just recently maybe this past month I been more into to just wanting sex then I finally realized that we have sex some what a lot but his dick isn't always hard even sometimes when I'm giving him head which upsets me cuz I be so into it I just be wanting him to fxck that shxt outta me or me fxck the shxt outta him.. Any ideas or advice on this!!?