Wasn't felling heathy/Wasn't feeling well/not feeling good/Felling ill/Feeling sick; Using a bathroom number 2 four times a day, regular stool not soft; Back hurt; Slightly dizzy; I worry about how I am feeling until I know it is from the shot or not I am not going for another shot; Maybe nauseous; Feeling down; This is a spontaneous report received from a contactable consumer (patient) reported that: A 79-year-old male patient received BNT162B2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Solution for injection, Lot Number: EW0123; Expiration date: unknown), via unspecified route of administration on 02May2021 (at the age of 79-year-old) as first dose, single dose COVID-19 immunisation. The patient medical history included atrial fibrillation and the concomitant medications included blood thinner for atrial fibrillation. The patient took pfizer shot 3 weeks ago. The patient experienced was not felling heathy, I wasn't felling a 100 percent; Was not feeling well/not feeling good, using a bathroom number 2 four times a day, regular stool not soft, back hurt, Feeling ill, Feeling sick, Slightly dizzy, worry about how he is feeling until he know it is from the shot or not, patient not going for another shot, May be nauseous, Feeling down on unspecified date in May2021. The patient stated that he got the shot 3 weeks ago and patient was due for second shot tomorrow but he have a concern, he do not think he is going for it, 2 days after he was not well about 8 days and then he felt better and then about 4 days ago he felt the same thing again, The patient stated that "he did not really care to report it but what he was calling to see his second shot is tomorrow and he is not going for it, but he would like get it may be when he feeling mentally after it, Could he take it couple of weeks later, if that ok?" the patient had a reaction to the flu shot (Unspecified Flu Shot) and he was feeling ill for about another 9 days it went away, but then it came back 4 days ago; didn't feel well/ not feeling good. The patient was scheduled for my second shot this morning I did not go because he is not feeling that great. The patient said he got the flu shot 3 weeks ago and 2 days after this shot, he did not feel well for about 7, 8, 9 days and then it went away, he felt okay and then about 4 days ago he got back the same feeling, not feeling good, slightly dizzy, maybe nauseous. Using the bathroom, number 2 frequently 4 times a day and he was scheduled for my 2nd shot this morning I did not go because he was not feeling that great. The patient stated that he took the vaccine three weeks ago and he was scheduled for his second shot this morning, he did not go because he is experiencing some side effects(Further not clarified hence captured as verbatim) and he was concerned to see this is related to the vaccine (confirmed as Pfizer COVID vaccine) or not?" He got this vaccine shot 3 weeks ago two days after he was not feeling well, he was feeling down for about 8 or 9 days and then it passed, the patient felt better then 4-5 days ago the same thing come back, this is 3 weeks now. The patient did not receive any treatment for the events, the outcome of the events was not recovered.  Information on Lot/Batch number was available. Additional information has been requested.