What if I can't satisfy my older girlfriend?

It is well worth trying to talk about sex before you actually have it.

I am 28 and I have a new girlfriend who is 44. I am worried that she is much more experienced than me and I might not be able to satisfy her in bed

Your concern is admirable but unnecessary. Being 44 doesn’t turn a woman into a sexual diva and your new girlfriend is likely to be just as anxious as you are about being judged on her sexual performance.