High BP, Taking Atenol, Also Going Through Pre-menopausal. Will This Affect Cholesterol And Kidneys Long Term ?

I have been diagnoise with high blood pressure . I am using Atenol I take 50mg in the morning at 6:30am and 50mg at 6:30pm due to the fact it wears off after 12 hours, sometime after 6 hours. I started with this medicine almost a year ago starting at 12.5, 25, 37 (this was a pill and 1/2) and now 50/50. I check my pressure a lot because I feel funny and 75% of the time when I feel funny it s high ranging from 145/92 -150/100. I am ablack 49 year women with Ulcerative Colitis which is doing great since 27 bascially healthy. Feel great, but also going through pre-menopausal. I really do not think this medicine is working for me and I do not want the doctor to prescribe fluid pills. I am already a small frame women and do not want to lose weight taking fluid pills. I want to change my medicine, I really think something else will work. Also is it dangerous to take this high dosage, will it affect my cholesterol and kidneys long term?