Should I ring or wait till tomorrow

Hi I was referred to dermatology last week Monday as the 2 week rule due to a mole on my back that's been itching and been sore. I received a text on Thursday from doctors saying when the referral was made there were no appointments available and if I don't hear from the hospital by Monday 23rd August to give the hospital a ring. I've got the nhs app downloaded on my phone and have checked a few times today but still nothing showing apart from the referral been placed. I'm getting more and more anxious each day and struggling to function. Should I ring the hospital now or wait till towards the end of the day or tomorrow. Scared of being told off if I ring now and ask when I will get an appointment.