If this is something you still want to do, then you should keep trying. Your age is not an issue, so put that behind you. I understand where you’re coming from with the finances as well. I think at the end of the day, it will pretty much be a wash in terms of income for me (at least until the loans are paid off), but as you said, it’s not about that.
That said, I would advise that you sit down and thoroughly review why you’re having a tough time with your coursework. Is it difficulty understanding concepts? Are you getting thrown off with calculations? Are you not devoting enough time to your studies? What have you tried in order to succeed in your courses? Are you studying in the right way? Is there any help available to you (tutors, etc)? Are other distractors getting in the way (personal life, work, etc)?
If you’re going to attempt the coursework again, come up with a plan about what you’re going to do different this time. If you just try the same way over again, you’ll likely get the same results.
That said, Organic chem is a much different course than Gen Chem. Organic is a lot more conceptual, and not as numbers-based as Gen Chem. You might find it easier, depending on where your strengths are, but obviously, you need to get past the Gen Chem hurdle.