As a developer myself, I would recommend you not to restrict yourself to JAVA, PHP or any other language. New Tools/languages keep coming every day. If you do plan to move to freelancing. PHP has a lot of options in the freelance space and a lot of competition too.

Learning PHP is as simple as learning any other language. It depends merely on your interest.

Personally if you can code, you should not restrict yourself. I have had to code in many languages, PHP, Perl, shell script, Python, Java, Javascript, Ruby etc... I would keep your developing skills and logic, algorithms etc.. and increase your knowledge and experience in the different languages.

I agree with you JAVA is a lot more time consuming. But it also has its enterprise level scope.

At the same time learning a new language should not be a barrier for you to stop exploring what's out there and keeping your skills up to date. Learning new technologies should be your primary focus and getting project out of your stack helps you build a good reputation.

There are many options for you to pursue. Having an open mindset will help you move forward. If you look to learn now, you are setting yourself up for a brighter future.