Sorry to hear you're in pain. From what I have read (obviously take this with a grain of salt), that could potentially be a first symptom. But that pain as you have described it so far, especially for only three weeks and without anything affected beyond the foot, could still be many many things. There are many hlab27 positive people who do not develop AS or any SpA, and some with those diseases who do not have that gene, so it is not a definitive test either.
I hope you find some relief soon! Also, you may want to post this on the general forum - it gets a lot more traffic.
Mid-20's. Undiagnosed upper and low back/SI pain (along with hips & ribs consistently, and neck, knees, heel/bottom of foot, ankles/achilles, and wrists periodically). Diclofenac 75mg 2x/day and Prilosec 40mg 1x/day. PCOS recently diagnosed.