No you bloody well don´t.
a) Losing 1.5 pounds a week is a normal amount when you´re still pretty heavy.
b) You´re just changing from eating wayyy too little to eating sort of, kind of of enough for someone who´s trying to lose weight, is it any wonder your body needs time to adapt? Please don´t go back into starvation mode or you WILL find that the weight comes right back on as soon as you start getting closer to your goal weight. Your body needs resources and denying it those won´t help you in the long run, physically or mentally. We have solid studies that show that getting to a healthy weight with a crash diet (which is what you were doing when you weren´t even reaching 1500 kcal/day) will leave you with a permanently lower burn rate which makes that normal, healthy weight almost impossible to sustain. It´s your decision and all that but please please please be sensible. You´ve already accomplished a LOT and even your GP agrees you should take it easier now. If you want a bigger deficit: go for daily walks.