PAINFUL LUMP IN LOWER EXTREMITY OF RIGHT LEG, LUMP ON CALF IS BIG, SIZE OF SOFT BALL ON  BACK OF CALF, AND STICKS OUT AND IS PAINFUL / SORENESS IN LOWER EXTREMITY OF RIGHT LEG; VERY SORE INJECTION SITE ON ARM POST VACCINATION; BLOOD CLOT IN LOWER RIGHT LEG; PAIN IN BACK; SEVERE ANXIETY; PAIN IN HIP; This spontaneous report received from a patient concerned a 38 year old female. The patient's height, and weight were not reported. The patient's past medical history included: blood clot in right leg (In 2010 and since has been on blood thinners), and concurrent conditions included: hereditary blood clotting issue, and other pre-existing medical conditions included: The patient was not pregnant at the time of reporting. The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: 1808980 expiry: UNKNOWN) dose was not reported, 1 in total, administered on 31-MAR-2021 to right arm for covid-19 prophylaxis. Age at time of vaccination 38 years old. The patient was previously treated with levofloxacin. Concomitant medications included apixaban and cyanocobalamin. On 31-MAR-2021, the patient experienced very sore arm for like 2 weeks after receiving the vaccine. The patient got a lot of shots (levofloxacin, Vitamin-B12 shots) and they did not hurt like the vaccination shot. On 10-APR-2021, the patient reported that she started having soreness in lower extremity of right leg and that soreness turned into a lump, Painful. The patient went to primary care doctor after pain started and before seeing interventional radiology. Interventional radiology performed scan in JUN-2021, results not reported. The patient was instructed to use compression wrap for leg and continued on blood thinners. MRI and biopsy has been scheduled. MRI (Magnetic Resonance Imaging) would be done to see if surgery is needs to be remove the lump. The patient reported that Lump on calf was big, size of soft ball on back of calf, and stick out and it was painful. She had to sleep with leg turned out due to pain and that was causing pain in hip and back. The patient had blood clot in 2010 in right leg as well but different type of clot this time. On an unspecified date in 2021, the patient experienced blood clot in lower right leg and hematologist thought that the blood clot may be due to vaccine. The patient reported that the Surgeon blew it off like it was a skin rash. The patient experienced severe anxiety over all this. Depending on results of MRI and biopsy, they might have to cut through muscle and do skin grafting. Doctors thought she was hypochondriac and treated her poorly. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from very sore injection site on arm post vaccination on 14-APR-2021, had not recovered from painful lump in lower extremity of right leg, lump on calf is big, size of soft ball on back of calf, and sticks out and is painful / soreness in lower extremity of right leg, blood clot in lower right leg, pain in hip, and pain in back, and the outcome of severe anxiety was not reported. This report was serious (Other Medically Important Condition).; Sender's Comments: V0: 20230125133-blood clot in lower right leg. The event has an unknown/unclear temporal relationship, is unlabeled, and is scientifically plausible. There are other factors more likely to be associated with the event. Specifically: MEDICAL HISTORY. Therefore, this event is considered inconsistent with vaccine administration.