I did that myself, and have certainly regretted it at times. The teaching part didn't work out for me, because I found that once I had my teaching certificate, since I didn't actually have an education degree to back it up, it wouldn't transfer to other states, and even with a full year of high school teaching experience, I would have had to repeat the certification process once I'd moved. Also, as far as I know, there is no such thing as a paid student teaching position. However, with the Masters degree I earned, I was able to get into industry and am spending a long career in medicinal chemistry, although my job prospects are capped without the PhD.
Without a PhD, there are simply some jobs you will not be able to get. At one time, experience would make up for it, but now, that happens very, very rarely. If you never want the type of job that requires a PhD, there is no reason to get it and having one may make it hard to get other jobs; but if you can get one within a year, and you might want one of those jobs, get it now. Either way, you will have to re-dedicate yourself to your education. Take some time, think about what you really want to go for, and when you've made a firm decision, throw yourself into it and let the other pathway go.