Reading the note wrong and thought MD note was an order

So the story goes like this. I am a new nurse for about 8 mths now. The patient was having febrile neutropenia with 2-3 episodes of a spike of temp at night for the past 2 weeks, no sign of infection, have cancer, and was getting chemo. The nurse last shift told me not to give the meropenem if the blood culture was negative in the shift change report. I re-read the MD note and I thought the MD note also said that and I took the note as an order (Apparently I read the old note, the MD added a note saying to continue the abx after, which I did not read). The blood culture was negative, and I did not give 2 doses of the meropenem as a result. In the day shift, my buddy nurse texted me and told me the family was upset that the pt missed the 2 doses of abx. The family was very upset and the pt was crying over missing the 2 doses of abx and that I did not give the 2 doses of abx without an order. The day nurse received 6 phone calls from the family. The MD and the day shift nurse had to apologize. I think the pt received the final dose of abx today from the day shift nurse in the end. 

I feel like I got no one to talk to that could empathize so I am writing here. I feel sorry for the pt, the family, the MD, and the day shift nurse. I feel like I let them down and it was dumb of me. I know that I can't blame anyone because I am the one making the final decision. Though I feel sorry, I am also scared about what will happen to me and if the pt will be okay. What do you guys think? I just want the honest truth and not just comforting words. ?