I am also sorry to hear you are going through this. And I'm sorry for the loss of your father.
SSRIs do take weeks to reach effective levels. And while I believe in meds, broadly speaking, GPs don't know squat about mental health issues. I would find a psychiatrist and get an initial consultation. This consult should not be 15 minutes. My first visit to a pdoc took nearly three hours. He went through my entire history, both medical and mental, he asked dozens of questions, and only then did he offer a diagnosis and treatment. And he would never, ever have said that should be over anything by now. That is hacky.
I didn't see him for panic, though. I saw him for bad OCD and depression. Several year ago I did have daily panic attacks for like three months or so. I too was at my wits end. I started working with a Cognitive Behavioral Therapist and it's been years since I had a panic attack.
Someone once told me that after you have one panic, every panic attack after that is from fear of having another panic attack. I buy that. You can, and will get your life back. Whether it's through CBT or meds, or a combination of the two, it will absolutely happen. But it won't be through your gp. Ask around, find a professional who specializes in this. Seeing your GP for a mental health issue is like seeing your GP for cancer. Frankly, your GP shouldn't have even treated you. Can you imagine your GP saying, "well, I think you have heart disease, so I'm going to open up a vein in your leg, and with an orthoscope I'm going to wind my way up to your heart to put in a stent." No way! He'd send you to a cardiologist! But because it's mental health, he thinks, "oh, I'll just shove whatever old med I've heard of and tell her to get over it." It's BS and it's upsetting. Find a specialist who knows all meds and treatments available.
Hang in there. You'll pull through.