Losing too fast?

ridge4mfp

Hello all, a little background first.

I started my fitness journey in mid-July of this year, when I reached my maximum weight of 286. I am a 59 year old female. I completely changed the way I was eating, and started classes (water aerobics, yoga) at the local YMCA.

I did not discover MFP until mid-September or so. I began logging two weeks ago and have had a food scale about a week. I set my profile to 1.5 lbs per week goal. After an initial misunderstanding, I am also eating back my exercise calories (50-75%). My current limit is 1540 calories per day, although I don't regularly hit that. I tend to average around 1350, but am careful to not eat below 1200 net.

Before joining MFP, I was averaging about 2lbs per week loss. But that has suddenly seemed to accelerate. I have lost almost 5 lbs in the last 7 days, and my current weight is 258.6. Should I be concerned? I read that it can be faster for the morbidly obese, correct? I am certainly not complaining, but want to make sure I am not losing at an unhealthy rate.