Your story is yet another example of home owner risk. You concluded that "landing a stable job" actually gave you the option of buying safely. It did not. Five months of income is not an assurance that you can pay-off a six-figure debt over thirty years.
However, your decision was not a bad one. It was driven by family considerations and a desire for stability. I get it. If the property appreciates in value, you can sell and move when your kids get out of high school, relocate and pocket the difference. That would be a great outcome and it is in the realm of the possible. So, not all is lost.
In the interim, I'd suggest the following. If the cash flow cost of your mortgage is the same as your previous rent, your after-tax of housing should be less. After all, your interest expense is deductible (assuming a loan of $750k or less) as is your real estate tax expense. Put those amounts toward your mortgage reduction. Don't spend the savings!
Second, I woud definitely try to find some kind of online "gig" work -- no more than a few hours each week. The easiest place to start is Amazon Turk https://www.mturk.com/worker
Third, I would not recommend that you consider becoming a beginner in a new industry. Rather, given your existing skill set, what additional skills could you credibly acquire that would increase your ability to generate MORE income? Your job is to increase the amount that some employer will pay you. It makes no sense to take a new job that pays you less than you are currently earning. Doing so just makes your financial situation that much more riskly.