There is no clear research data on whether the Covid vaccine affects the menstrual cycle in the average person, and there have not been studies of the effects of the Covid vaccine on PMDD. The vaccine does not appear to affect hormone levels. If you feel that your symptoms are worsening following the vaccine, your symptoms will need to be treated on a case-by-case basis. Be sure to bring up any concerns about menstrual or PMDD changes with a trusted healthcare provider.
On the other hand, there is mounting evidence that moderate-to-severe COVID infection, which is more likely if you are not vaccinated, can cause long-term emergence or worsening of symptoms that may overlap with PMDD (e.g., mood symptoms, dysautonomia, physical symptoms) among other health problems.
If you have specific concerns about the vaccine, write them down and bring them up for discussion with a trusted health care professional who can help you determine whether the vaccine is right for you.