Trigger and bfp

Hi ladies! Any help would be great. Please be kind I’m new with the whole trigger shot business. So I tested out my trigger with the easy at home brand and had negative tests at 11 days post trigger. I ran out of those tests so I tested just now with a FRER and I see the faintest line. I know all tests have different sensitivities but could this be the start of a true bfp or most likely the trigger shot still? Today is 13 days post trigger. Thanks! Baby dust to all.