Newly on birth control

I just started on birth control. I’m 16. I am about 3.5 weeks in and I was on my period the first week I started. The past couple days i’ve been having brown discharge. There is no smell or anything else. And then today I had like heavy spotting but I haven’t gotten to the sugar pills yet. I talked to my mom about and she said she thinks it’s just all the new hormones and I recently started swim and my grandma recently passed so she thinks my body is just going through a lot. I just wanted a second opinion. I’m calling my dr on monday to get her opinion too.