I feel I caused my father's death

My father passed away 2 months ago. He was a pneumonia patient and had BPH (prostate enlargement) for almost 2 months. Due to his lifestyle, his recovery from pneumonia was very slow. He refused to go to hospitals for checkups, but I forcefully took him to the hospital and did everything possible to aid in his recovery. I was the bystander and he was in ICU for 1 day and admitted for 5 days. Then they discharged him and he was under home care for 2 months with bi weekly checkups. 2 weeks before his passing, my mom asked me to buy his prostate medication (Geripod D), which included Silodosin (8mg) and Dutasteride (0.5mg) tablets. I showed the prescription on my phone to the pharmacist, and they packed a strip of 10 tablets. However, they didn’t include any dosage instructions on the package. On my way home, I doubted whether the dosage was correct but thought I would verify it against previous packets at home once I got there. When I reached home, I handed the medication to my mom and completely forgot about checking the dosage. That night while I'm working, my mom asked me whether the tablet should be given now (he had medicines to have on morning and night), and I told her yes. The next day, I had a minor accident and was wounded, and i completely forgot to followup this. A few days later, my mom asked me to buy more tablets. I wasn’t able to leave the house that day but went to the pharmacy the next day to purchase the same medication. Remembering that the pharmacist didn’t include dosage instructions the first time, I specifically requested them this time. At that moment, I realized the tablet was meant to be taken only once a day, at night. When I calculated the previous usage, it turned out my dad had been given the medication both in the morning and at night for 4 days, and one day he didn't have any since i didn't went pharmacy. which would explain why the tablets ran out when they did. However, my dad did not show any immediate reactions, so we forgot about the incident. A few days later, we had a checkup for his pneumonia, but the doctor didn’t mention anything abnormal. Unfortunately, the urologist was unavailable that day. I later called the urologist but forgot to mention the dosage error, as my dad hadn’t shown any concerning symptoms. A week after the incident and 3 days after last checkup, we found my dad had passed away in his sleep one morning. My mom and sister recalled hearing him cough early that morning but didn’t take it seriously since he had been coughing for decades. We rushed him to the hospital, where the doctor said he had likely passed away due to either cardiac arrest or community-acquired pneumonia. Now, I am consumed by guilt, wondering if the overdose of the medication contributed to his passing or if his pneumonia was the cause. I spoke to the urologist afterward, who assured me that the medication wouldn’t affect the heart, but I can’t shake the feeling that he might have said this just to comfort me. I have been searching the internet for the side effects of the tablets and any possible connection to his passing, but I still can’t find anything that satisfies my mind or eases my thoughts. I'm 23 and this the first time in my entire life going through these much anxiety and guilt. I took one therapy session which helped me reduce my anxiety. Right now my self and my mother at home. My father was not that close to us.But this was very unexpected. and whenever I feels like I'm alone or remember about my father these thoughts comes to my mind and I blame myself.