[URGENT] What free resources can take measurements on an at-home EKG?

Long story short, I have a Kardia Mobile EKG as I have to worry about medication interactions causing abnormal heart rhythms. The main concerns being serotonin syndrome and prolonged QT interval - my doctors/prescribers all know of this issue and have assessed that the treatments are worth pursuing, but I still need to be careful.

I recently started a new medication that risks those interactions further. I need to calm my growing anxieties about whether my most recent EKG displays any rhythm abnormalities. However, I would rather avoid paying for a cardiologist to review through the app, and I also cannot financially afford unnecessary emergency medical expenses (an actual medical emergency is one thing, but me acting on my anxiety without justification is another).

Does anyone know of any free resources that can take measurements on a PDF copy of my most recent EKG? Could someone teach me how to take those measurements myself (I am an engineering student, not a medical professional)?

TIA for any advice/information! I will try to keep a close eye on this post to answer questions.