achy left arm from shoulder to hand at work :/

For the past few weeks my left arm has been super achy all the way down to my hand and I've had occasional chest pains but today I'm at work at my desk and it's super achy I had a panic attack this morning then felt ok and my hand hurts as I type. I am scared it's my heart and wanna leave work so badly. I'm holding an ativan under my tongue right now. Today has just been super weird feeling and foggy. my heart is going super fast even sitting down. I feel clammy. I had a full heart work up in January and several ekgs since and a holter monitor. I am trying so hard not to run out of work. I'm not sure what is with today...I'm super dizzy too with an upset stomach :/.

Thank you! I am lucky to have a slow work day today so I've been on all the resource pages. I'm too young to feel like this! I feel like 25 is a stressful year though with figuring out where you want to be in life and its just been a rough year.