I find that flying solo is very different from a duet. The biggest difference has always perplexed me. To put it bluntly, the output is a lot thicker when going down the DIY route, more like wallpaper paste. not the sort of thing you can ask at the doctors.
Doctor: "So Mr Lube what seems to be the problem?"
Me: "well, when I masturbate my cum seems thicker then when I am having sex with my partner, is this normal"
Doctor: "Mr lube get out of my surgery and come back when you have had the therapy you so obviously need"