It sounds very complex, but let’s see if we can sort it through. The first thing I would do is look to see what services might be available for your girlfriend. I would check your local hospital to find out what they know about helping unmarried teenagers. Typically there are many counseling, medical, and infant care programs that are available. You do not have to figure this out alone. I would encourage your girlfriend to check out the same resources at a local hospital or Planned Parenthood site near where she lives.
Second, your apprentice program should have a way of getting you networked into the field you have chosen. Get busy networking yourself into your chosen field so that even if you have to take another job right now, you will be ready when the opportunity to join your profession comes along.
Finally, let your parents help. Family is there for times like this. Let them help in whatever way they can.
You have the desire to change and be more than you are right now. This is a very good thing. That kind of motivation will help you look at what needs to be done, and find a way to make it work. I would get the counsel of family and the experts at the hospital so you and your girlfriend can make the best decisions possible.