I think if you have any misgivings....... at all..........whatsoever...... about the future viability of your relationship, then you might consider not making it harder to end that relationship. Children make a relationship harder to end. A marriage certificate makes the relationship harder to end. Intertwining your finances makes a relationship harder to end. Whatever the commitment level is right now, stop adding further commitment if you're having doubts.
That said, give it a little time. Not so much time that you're sacrificing a significant portion of your life, but enough time that you can realistically say you approached the root of the problem. Have a talk or five with her about all the things that concern you. Ask the hard questions. Make sure that you know it's not going to work, or maybe it's just a misunderstanding. Be anal-retentive about making sure you're on the same page.
If you've done all that, and afterwards you know that you're not compatible, then you're just incompatible and that's that. If that's the case, then break it off as soon as you can, and start dating again. Don't stay with her just because it's comfortable or nostalgic.