Hi I've been on phentermine 37.5mg for almost 2 months now and I never had a problem with my period. I always get my period sometimes I'm a day or two late but I always get it. I had my period September 21, on October 23 I did a pregnancy test and come out negative and that week I woke up in the middle of the night to throw up something that never happened before o Lu when I was pregnant with my son, I was nauseous for about 4-5 days. Then on October 30 I did another test and came out negative. Today is November 2, no period but I'm having very sensitive breast as if they were getting fuller and also pelvic discomfort, some pain here and there. Can it be the diet pill "Phentermine" effecting the results on my test?