I was 135lbs and I gained 16 pounds in 1 week. is it wrong?

Is abnormal to gain so much weight in a week; granted, you could be on your period and have some water retention; I have seen females go up 6 pounds or so but they come back to their normal weight after their cycle is over. Are you sure is been 16 pounds in a week? Cause if so, indeed, you have to make a doctor's appt. If it's been over 3 weeks then what are you eating?

I once put on 10 lbs in 2 weeks because I was eating pizza and pasta 2 times a day for a period of 7 days. I got back to exercising and eating normal, so it was not a problem.however 16 lbs in one week is something to be concerned about cause is not really normal to put on that much weight, unless of course, you're training for soem event where you need that much weight, and you're eating accordingly to achieve it (boxers, wrestlers and such); I would encourage you to really take a look at the period of time though to really determine if you gained that much in a week; also weigh yourself with another scale.

if you want to lose weight just eat a healthy diet and exercise and to make it fun get a bunch of friends together and go play volleyball at the beach or soccer.

Your thyroid may not be working properly. Or if you binged all week, it could be possible that you just gained it all from not being active and binge eating. Still though, you'd have to eat a ridiculous amount to gain 2 pounds a day. It doesn't sound too healthy. I suggest you go to the doctor.

Did you change your eating habits? That's a lot of weight to gain in one weight so something has to be different or wrong. I would see a doctor or a nutritionist to get back on the right track the healthy way. Don't take any pills- you may lose weight but you'd gain it right back when you stop taking them and they can have serious side effects.