I actually started out a lot like this guy - dabbled with C++ and Javascript early on (back in web 2.0), gave it up, then wanted to do a business but didn't want to/couldn't afford to pay $15k for a bespoke e-commerce website. So I taught myself basic PHP and started using WordPress. Simple enough. Then I realised WordPress is too restrictive. So I learned more PHP and picked up some advanced OO knowledge, and moved to enterprise level framework (S2).
After that I became more interested in JS because now you can use it in the backend too, so I started to learn that. Now I'm getting into Java.
I feel like if you want to just hit the ground running, PHP is a better option than Java, coz it's really dummy-proof. BUT, like davidktw has said, Java is THE language to learn if you want to get to the absolute highest levels of software development, whether it be web or native. It can be VERY frustrating though, especially if you're not used to being very careful about data types.
So I think if you want to learn just enough programming to get yourself a functional e-commerce site, then PHP/WordPress will do just fine. If you want to become a professional full-stack developer, you'd best learn Java, grind through the hard bits and you'll be better for it. But I do get the sense that you're more interested in business than technology per se, so maybe PHP is the better option for you.
