Everytime we have sex I lose focus.

Hi sis dolly! I am a lady of 23yrs, with no children. I’ve been in a relationship for 3yrs now, and am engaged with a guy of 28yrs. My problem is that every time when we have sex, something has to come in my mind, I will think of something happened in the past, nothing serious. Then I start losing focus, and that thing it’s keeping us distance now. The thing is that I thought that I have a libido problem which usually effects guys. If a guy has a libido problem then you can just see if you’re eligible for a prescription of testosterone and see your sex drive improve a lot. But sometimes it’s not as simple for us girls. I even bought the pills called libido boosters, but still, this thing keeps distracting my mind, and nothing bad happened to me in the past that I can think about, I don’t even have stress at the moment. A few friends of mine have recommended using spanish fly pro to see if it can help boost my libido and keep me focused. I’ve been thinking that maybe it’s just because we’ve not spiced things up in the bedroom recently so I might look to introduce a few new techniques and maybe toys to get things going. I’ve always been nervous to do this though so that might be my backup… What possibly can be the cause and what should I do?