TDEE/BMR, am I totally doing this all wrong

I totally get the whole eating back your calories and eating at LEAST at my BMR, but I'm getting some conflicting advice.

My BMR is 1700. Which sounds like more than enough calories in a day, this is true. However, given that I am 5'2", 200 lbs, and have PLENTY of body fat that needs to go, am I really doing myself a major diservice if I am eating between 1200-1500 calories a day, at least for now?

I've been there. From a 2500 usual I went down to 1300-1600 a day with a lightly active workout. I indeed lost weight at 2 lbs a week. It was good for over a month or so when I came on a plateau. I also was lifting then but was doing a lot lighter weights since I lack energy to do it. So I asked a trainer and he told me that I might have ruined my metabolism by cutting that much just to lose at a faster pace. Now I'm struggling to get back into my usual 2500 and its really hard. My body got kinda used to eating less so I feel bloated most of the time. I'm on my 2nd week in repairing my metabolism and energy and am eating at 2230 cal a day. I add 100 cal every week or so if I see a good rate of loss like .5-1 lb per week. I'm also back to lifting the heavy weights like before but still struggling with it since I'm still rebuilding my strength too.

I guess its really up to you which path you want to take but usually the one that takes longer and is more dedicated will be the better path.