How long between exposure and to herpes and initial attack?

Ive been with my boyfriend for three months and we have a good relationship. Anyway last week I started feeling really itchy down below and initially thought it was thrush, so took the trush treatment and we carried on having sex on most days. I noticed I had one small spot but brushed it off as being a shaving cut, anyway by the thursday/friday when we wer on the phone he said he'd noticed he had loads of spots that looked a bit like the spots you got on your face all along his shaft, and then by the saturday/sunday I had the same. Mine are even more severe and we have both been diagnosed with herpes. Now initially I thought he'd given them to me as about 1-2 weeks ago he had HORRIFIC mouth sores/cold sores n he did perform oral on me (stupid i know), so i just thought he'd given them to me n then id given them back..however ive just read that this isnt possible because if you get cold sores it cannot be transferred back to your own genitals if youve always had them (which he has) as your body would have produced antibodies, so that doesnt explain why we'd both have it...at the same time. I have been a 100% faithfull and i trust him but this is a bit strange as everywhere ive read said you'd get symptoms in the first 2-14 days and i THINK this is his first aswell because last night hed had two that had randomly appeared on his stomach and if your already immune (not your first attack) this is unlikely to happen. Its not impossible that I caught it off my ex cause he did cheat on me but we broke up 6 months ago, what is the likelyhood that one of us have been carrying it for a while n this is the initial attack? Please help im losing my mind xxxx