I was positive for corona virus beginning of this year, got vaccinated in april, for the past few weeks i had a buzzing sensation in my head, sometimes worse than others, is it an after effect of the virus? what can i do, should i be worry, see a dr?

There are still a lot to learn about the post Covid-19 syndrome as well as the adverse effect of Covid-19 vaccine. If the symptom waxes and wanes, does not interfere much with your life, keep observing it, your doctor probably does not have any answer and you should not worry too much at this point. However, if symptom gets worse it could be a completely different problem, see your doc by then.

Your "buzzing sensation" is most likely tinnitus, and several cases of this problem following COVID-19 have been reported. Would suggest an evaluation by an otolaryngologist with audiometric studies. Not clear if this will spontaneously resolve on its own.

Since the virus can affect any part ones body, it's uncertain whether or not the symptom is COVID related. It's best to see your Dr, a neurologist or an Ear/Nose/throat Dr. for a proper evaluation.

It is unlikely that your symptoms are related to either testing positive for COVID earlier in the year or caused by any of the mRNA vaccines. I suggest that you see an ear Doctor.