Water in gas tank?

[oakley]

I have a 2017 Forester. I filled up with gas yesterday and drove approx 75 km. The drove again approx 50 km. No check engine light came on. This morning I went to start it and the check engine light was on as well as the cruise control, hill ascent and Xmode indicator. Then I noticed that I had forgotten to put the gas cap on when I had filled up yesterday. My vehicle was in the rain for a few hours last night, but I had driven the 50 km second trip after refuelling without any indication of any issue. I put the cap back on and started my vehicle again but the lights are still on. Reading my manual, this may take a few trips before the lights go off. My biggest concern is rain getting into my gas. Is there some type of stopper or flap in my gas tank opening when I fill my gas to prevent anything from getting into my gas tank? If so, then I'm confident the lights will go off in the next trip or two, but I was concerned about water in my gas. If there is a possibility of water in my gas, what should I do? Thanks