I've done the same thing. I drove 45 minutes to a rail trail only to discover I forgot my shoes. I have candie pedals, so I was able to ride with sneakers, but it was hard not slipping off, but I refused to go home.
Now I have a huge Coal bag that is just for bike stuff and I always keep my stuff in it. I find that works great.
See your not the only one who has duh moments.