Not seeing it in person is difficult to tell but it could be. There almost looks to be a rusty brown edge to the urine stain which blood in the urine can show even if the actual urine area is not pink tinged.
Old blood is rusty brown coloured, fresh blood is pink or red depending on the concentration.
It is very possible to have a urinary issue and have yellow looking urine with a pink, red or rust spot in the middle.
My Kei had a very low grade UTI one time presenting with sporadic pink urine, dark spots both pink and rust coloured, rust coloured edges to her urine and most of the time, nothing. We had sterile urine draws done and blood never showed up in her urine nor did bacteria. She was put on two type of antibiotic neither which worked but a sensitivity could never be done because bacteria never showed up.
Finally as a very last resort she was spayed even though the vet and we were certain this was not a uterine issue. It wasn't. A perfectly healthy uterus was removed and she continued with the sporadic bleeding.
Finally, the vet suggested Hills C/D. It changes the ph of the urine making it hospitable to bacteria. One can later and no more blood and she never had the problem again.
Since Spike's can possible uterine it narrows down the problem. I'd have a sterile urine sample drawn and checked and go from there. If nothing shows up, try a can of Hills C/D.
