I Am A 59 Year Old Black Female That Had

I am a 59 year old black female that had a total knee replacement in December 2015 I lost 20 lbs I have now gained 7 1/2 pounds back and I am miserable because I felt so much better when I was smaller my problem is sweets and I want to lose about 25-20 more pounds my dr prescribed me diethylprop 75 mg my first day starting this diet was sunday I dnt feel bad and had a slight headache is this a good diet pill for me to be taking?