std screen results worry

Lu

i went for an std screen last monday and got results texted thru this morn saying all negative. when i went i had my blood taken and then was sent to do the swabs but i was on my period and just put them in the bin cos i got scared.. anyway i got another text this afternoon saying "There has been a problem processing your sample for testing" its too late to ring the clinic now and now im freaking out thinking theyre gonna tell me ive got hiv (i havent been at risk but i have major anxiety) what could be wrong???