Hello. I just recently started taking Adderall XR about 3 weeks ago, starting at 10mg once daily and now 20mg 2X daily. I also have been taking lexapro 20mg for the past 7/8 months. I was supposed to get my period about 6 days ago and still have not gotten it. I have been feeling the symptoms of my regular period though such as my moody-ness and cramps (although the cramps haven t been as bad as usual). I took a home urine test yesterday and it was negative. And yes I am sexually active but use condoms . I read another answer on here to check your thyroid but I just recently had a blood test for that purpose and the results were negative. Another thing, I have lost about 5 or 6 lbs since I started the Adderall. I am not stressed, at least I don t feel stressed. Could you help me find some answers, please?