8 hr post vaccine, typical side fx (fever, headache), but also significant bi-lateral leg cramping and spasms that continued for 6-8 hours.  Spasms were prominent in inner thigh/groin and down entire legs.  Legs were not movable (heavy), difficult to get out of bed or walk.  Very strange and nothing like this ever experienced before shot. Fine next day.  Around 4/9, pain began in ball of R foot in the AM, hard to walk.  Over next few days, pain extended up to medial posterior calf (very painful), back of knee and groin.  Unexplained bruising on lateral calf.  4/20 woke to swelling of R leg (ankle, posterior knee, groin), went to Urgent Care that night and was sent directly to ER for DVT symptoms.   ER Ultrasound showed no clot, was sent home.  Pain continued to increase, with burning and difficulty walking.  Second Ultrasound done 4/22.  No clots found.  Pain continued to worsen, with swelling/aching on front of calf and severe foot pain.  Veins/skin tender.  Painful groin spasms happen again, same as night of shot.  PCP ordered ABI and spine Xray.  ABI was normal.  Xray showed same issue as 29 yrs ago (prior known L5S1 anterolisthesis; have not had back pain for many years...when I did, it was localised to spine and sciatic in the L hip, was not at all similar to these current issues in R leg.  perhaps related if inflammed, but is vastly different in symptoms and unlike past history).  Saw Vascular Surgeon 4/30, ordered abdominal CT Abdomen Pelvis w IV Contrast.  results normal. arm bruising at IV and blood draw site.  Saw second Vascular Surgeon 5/4 who felt pain related to inflammation response and ordered CBC.  Platelets 178. (patient had requested this test starting on 4/20, this was the first doctor to order it).  Pain continued but some relief found with compression socks.  on 5/10 US Bilateral lower extremity venous duplex with reflux study was done on both legs.  No DVTs, but damaged valves and reflux in the external iliac common femoral vein and femoral veins proximal segment (worse in R leg)  and great saphenous vein at the sapheno-femoral junction (R only).  These areas are where the spasms are happening but doctor not able to conclude relation, wants neuro consult, could be nerves causing spasms. Doctor prescribed compression socks for venous insufficiency concerns, to be rescanned annually for life. Vascular test results don't explain severe pain in calf and foot and referred to Neurologist for 5/28 visit.  As of today, 5/22, pain is persistent.  Pain/swelling is reduced with use of compression socks but returns without them; walking is difficult in the AM and PM hours; night time spasms.  Have also had shooting pains in L calf, both forearms, and ribs (back).  These occur mostly in the evening (nerve?).  Taking magnesium & extra vitamin D seems to help some. On strict anti-inflammatory diet.  I'd really like some guidance for treatment and what to do about boosters - do I switch to an mRNA vaccine?  I am a very healthy active 49 yr old woman who felt fine before the shot, and now I've been in a lot of pain, working greatly reduced hours for almost 4 weeks.  Please advise on what can be done to help.  Concerned about permanent damage and how to handle future vaccines.  (also of note:  first menstruation period was skipped after the shot, second period came a week late and was very heavy with bright red blood.  I am normally extremely regular, mod-heavy flow;  also, the J&J shot I had was a "last shot of the day" extra dose.  I was offered it while having a routine physical.  Could it have been improperly stored, as the last leftover dose?  Very unlikely since it was a doctors office, but including this info)