can't get doctors note/evidence for extenuating circumstance, thoughts?

I have this online presentation i have to do in a few hours (10am) for uni. Is 10% of a 20 credit module. Woke up like an hour ago feeling really ill, cold sweat and had to throw up and I can't see how I'll be fit to do the presentation. Trouble is I don't know how im gonna be able to get evidence for this ec? I'm not registered with a doctors office here so i can't see how i'll get a doctors note as evidence, if that fails i don't know what other evidence i could even submit. Should i just email the module convener without evidence? theres another presentation slot available next week for people with ec claims to do the presentation (big course), but i don't know how lenient theyll be. thoughts and opinions appreciated

Many universities allow you to self-certify a certain number of extenuating circumstances claims each year. For example, here's what the University of Surrey (my first Google hit) says on the matter:
"Self-certified extenuating circumstances
Self-certified ECs are used when you cannot provide evidence for an evidenced application, but you still have a valid/recognised circumstance.
When applying for self-certified ECs, you must provide a written statement outlining the nature of your ECs and explaining how these have affected you and your ability to undertake the assessment(s) to the best of your ability.
You can submit up to three self-certified applications per academic year (one per academic Semester and Late Summer Assessment Period), and they can be used for all types of assessment.
Each application covers a maximum period of five University working days. You can select any number of assessments to include in your application as long as the submission deadlines/event dates are within five University working days of each other.
If you are submitting an EC for an exam this will always result in a deferral."
What uni are you at?

Many universities allow you to self-certify a certain number of extenuating circumstances claims each year. For example, here's what the University of Surrey (my first Google hit) says on the matter:
"Self-certified extenuating circumstances
Self-certified ECs are used when you cannot provide evidence for an evidenced application, but you still have a valid/recognised circumstance.
When applying for self-certified ECs, you must provide a written statement outlining the nature of your ECs and explaining how these have affected you and your ability to undertake the assessment(s) to the best of your ability.
You can submit up to three self-certified applications per academic year (one per academic Semester and Late Summer Assessment Period), and they can be used for all types of assessment.
Each application covers a maximum period of five University working days. You can select any number of assessments to include in your application as long as the submission deadlines/event dates are within five University working days of each other.
If you are submitting an EC for an exam this will always result in a deferral."
What uni are you at?

just checked department handbook and i get two self certify absenses for exams/coursework. Thanks!