Diagnosed Bipolar?

I was diagnosed with bipolar over a year ago. I fully believe the diagnosis, it makes sense and out of all the things I’ve looked into this just fits. However, my grandmother doesn’t think I have it because of the way I was diagnosed. Mind you have I a family history on my dads side of bipolar(this is the grandmother on my moms side so she doesn’t have it) The way they diagnosed me was by getting me to fill out a form confirming my symptoms. They told me I was a glaring red light for bipolar however they wanted to test me out on antidepressants first. Basically the plan was to put me on antidepressants alone and if they worked yay, however if I reacted negatively they said they would mostly likely diagnose me with bipolar. I had an extreme meltdown on the meds. My mood was out of control and I couldn’t function properly. After having a huge mental breakdown I went complete cold turkey(which I now know was really bad) When I went back to the doctor she ended up diagnosing me with bipolar and prescribed me with Vraylar. I no longer have insurance so I’m not longer able to take the medication, however when I did it helped a lot. I said all that to ask if this way of diagnosing is reliable? I really think this is it, and I just need to learn to work around this. However, if that way of diagnosing is inaccurate then it might be entirely wrong and I’ll have to start from square one again. Any advice would really help, and thank you for reading my paragraph :)