How do you know when something you love to do should just be your hobby and not a career?
This is a tough question and one only the individual can answer. A great deal depends on your perceived values and material needs. Will this provide you lasting satisfaction and will the financial opportunities satisfy your material needs? Sometimes you don't know this right away and you have to try out the situation. I was in education for many years, but I was fortunate because my creative side was satisfied through my personal love for decorating my home and my counseling skills. When I retired from a full time job, I pursued my interest in art full time as well and so my loves have been satisfied at various times of my life. You have a long time to pursue your goals. Everything changes and nothing remains permanent. Be flexible and open to opportunities of various kinds, and your life will be fun and rewarding during all of its stages.
1. Visualize yourself doing the thing that you love for a long span of time, say 25 years and think whether you'll be satisfied with what you gain during the process.
2. Think whether you'll be able to pursue your family expectations and will be able to take care of dependents , if any.
3. Contemplate whether money matters more or the satisfaction that you get on doing the job. If your hobby is less rewarding financially, you must consider whether you'll be able to earn enough as per your expectations.
4. Analyze how future proof the field you are trying to enter is. It does not make sense to go into 32 bit video game development even if you love playing old games simply because the field is obsolete.
Summing up, the entire decision making process is a series of conscious choices that will have a large scale implication on your life. Hence, choose wisely. Remember, your decisions might affect a lot of people around you.