However, if you experience a headache for more than four days, this may spell the warning sign of a blood clot, Dr Khan said.
Likewise, experiencing blurred vision and nausea for more than four days could also signal blood clots, he warned.
Other blood clot symptoms include:
- Throbbing or cramping pain, swelling, redness and warmth in a leg or arm
- Sudden breathlessness, sharp chest pain (may be worse when you breathe in) and a cough or coughing up blood.
READ MORE: AstraZeneca Covid vaccine: Are children at risk of blood clots as child jabs trial halted?
These were accompanied by low levels of platelets, which help form blood clots, in the body.
The MHRA also found other clotting problems alongside low platelet levels in eight people.
The UK’s regulatory body urges people to still get their vaccination when called to do so.
Investigations are under way to determine if the AstraZeneca vaccine is causing the very rare blood clots.
Earlier this week the European Medicines Agency said it was “not proven, but is possible”.
Am I eligible to receive a coronavirus vaccine?
The NHS is currently offering the COVID-19 vaccine to people most at risk from coronavirus.
Everyone aged 50 and over can get the COVID-19 vaccine.
You can book appointments at a larger vaccination centre or pharmacy now, or wait to be invited to go to a local NHS service.
The order in which people will be offered the vaccine is based on advice from the Joint Committee on Vaccination and Immunisation (JCVI).