Worried that my first jab hasn't 'taken'

[JammyHands]

I recently took part in voluntary antibody testing organised by the NHS as part of a study. I had had one AZ jab about two months before taking the antibody test. The result was negative: no antibodies. Now of course I am worrying that it didn't work. I didn't get many side effects - sore arm for a few days, and felt a bit tired. So is it possible the jab didn't work? On the other hand, is it possible that the test was faulty, although it gave a very clear negative result?

There have been threads where a few people got this and then were positive for antibodies on the test at 10 weeks. Try not to worry. Maybe test again afar the second jab?

Yes it is possible that the jab didn't take

It is also possibly you did produce antibodies, but they cleared quickly. The timelines you give make this sound unlikely to me, but in biology there's a hell of a lot of variation.

This is one of the reasons why the official advice is not to change how you go about social distancing regardless of vaccination status

I took 10 weeks to develop antibodies. I had zero side effects after either dose but have continued to test positive for antibodies now 6 weeks after second dose.