They gave me a shot of ceftriaxone and told me to continue
with the doxycycline. The ceftriaxone helped a great deal (swelling went down almost immediately) but as I continued the course of doxy the problem began to get worse again.
I followed up with a urologist. He put me on Cipro for 14 days, 500 mg PO BID. By day 11, the problem finally seemed totally resolved. 5 days after stopping the Cipro, I can feel it beginning to come back.