Work environment

I am kind of new RN in the community based ED, little over a year. We had a shortage of staffs during the shift.  Everyone was busy with their patients.  I was giving blood thinner, but before doing that I needed a PTT lab.  I always get a new line one other arm even before begin blood thinner.  The patient's family is keep asking questions why the patient is getting blood thinner and that etc. And saying I did hear anything(even though I heard doc explaining to the family).  

In top of this happening, I got a new pt on the other room.  Keep getting messages and a call to go in the room to triage and start the bipap.  I got the lab and start the med without creating a new line.  I  Went to other room.  PTT lab came and it was high.  I am thinking may be I got distracted and made a mistake on getting blood afterwards.  

I re-lined and lab on the other arm and send the PTT to verify.  I am overhearing other staff commenting on what I did wrong.  I am getting mentally tired worrying about my mistake and worrying about what other people says.  Keep douting myself when I do anything and makes me feel so small.  

I like working in ED and think I am improving.  But when something like this happen, I just wanted to quit.  I have so much anxiety every time I go into work.