Just need to get this out of me

I apologize in advance for gaps in my knowledge. I am newly hired in a cardiac unit and Im also a 3rd year nursing student with med/surg, maternity, and telemetry interpretation experience.

I only had 1 patient with CHF for three days 12 hr shifts and she was stable for the most part, until about 1 hour before shift change today. She started crashing. Her bp was very very low, she was symptomatic, and she had all the symptoms of decompensated CHF, plus possible cardiogenic shock (due to many of her symptoms, but most importantly low urine output). The low urine output has been occuring for all the three days I took care of her. The hospitalist today ordered to make her lasix iv direct twice a day instead of once a day, so after talking with my nurse, we gave the second dose of her lasix 8 hours after the first one was given. This was okay, however, she still did not pee at all. for my entire shift today, she only peed about 200mls. And she had a fluid intake of about 700mls.

When her blood pressure medications were due, I rechecked her vital signs and she was hypotensive 70s/40s when her normal is above 120 systolic. She had all the symptoms, as I have said. Many things started happening, RN ordered stat ecg and bloodwork and showed st elevations throughout. RN called the hospitalist and the doctor was not responding so RN gave me the phone to wait for the doctor. RN said to give the doctor report if doc answers because rn will be busy putting leads on the pt for bedside monitoring and doing a bunch of other things while we waited. the doctor picked up so i gave report and i thought it went alright but the doctor started giving orders and as a student i cannot write verbal orders so i looked for the nearest nearby rn (my rn wasnt there anymore) and a different rn took the orders. The pt got a bolus of Normal saline and more blood work ordered. shift change started and i charted as much as i could think of. the hospitalist finally came and this is someone who has never met the patient before. the doctor walked in the room, looked at the patient, told us to call her if she has chest pain, and did not even look at the charts or anything..

now that i am at home, I am overthining and now unsure if what i did was ok. I probably shouldnt have answered that phone because it was such an emergent situation? are CHF patients ok to have saline bolus if theyre hypotensive? what if they have congestion? am I at fault for any of these if anything goes bad? What if i forgot to say some of the information during that call? isnt the hospitalist supposed to at least look at a chart while the patient was still somewhat managing?

im just really worried that I might have stepped outside what im allowed to do as a student, especially not having an instructor. I was feeling a bit ok during the situation and still managing it fine even though i felt weird that the RN would leave that phone call to me. It all happened so quickly. and now after it all happened im really feeling uneasy and nervous. i dont want to mess up. please calm me down.