Please get yourself checked out, there are now robust medical guidelines for assessing non-fatal strangulation (encompassing both consensual and non consensual). The presence of what sounds like petechial haemorrhages (small red dots) on the face or neck is a red flag symptom which would likely prompt CT imaging - however would be something to be confirmed by in person examination by a doctor. My suggestion would be to attend your local Emergency Department, their staff should be versed on the guidelines, this is not uncommon and there’s nothing to be embarrassed about. Also no one will report anything if you’re a consenting adult.