Birth control side effects

For the past 3 years I've had a regular period until recently. A few months back I had a horrific period where I was dropping blood clots the size of my palm every hour. No exaggeration. I stayed home from school. Then I didn't get my period until a month ago and it was only spotting for 3 days. I went to the doctor recently and she told me to begin birth control if I get a crazy period like the clot one but my mom said there's too many side effects to birth control. Has anyone experienced life changing side effects from birth control?(I'm not sexually active either)