First - Congrats on the awesome progress you've made!
I think a lot of it depends on how you lost the weight. Are you on a really restrictive diet or have you made gradual lifestyle changes?
If you've been changing your overall outlook on how food and exercise relate to your life, you'll be fine. I'm in the same boat as you in that I started at 250ish and am now 175ish with 30 more lbs I want to lose. It took me about 8 months to lose all that weight and I've been maintaining that lose for over a year now because I've changed my lifestyle.
Granted for over a year I haven't lost the last 30 lbs I want to, but I know why and it's just that I haven't focused on weight loss and kept to maintaining for now.
So don't worry, you can do it and you'll be fine. You've had great success so far. There's no reason that shouldn't continue.