I don't think you can develop PTSD from that. Clinically, someone develops PTSD after witnessing or directly being involved in a traumatic event. There is a list of what is considered a "traumatic event." I know all about this when I went through the process of getting diagnosed for PTSD.
The severe episode of OCD is giving you flashbacks, but it does not sound like you were harmed or experienced a life-or-death situation. Nevertheless, the flashbacks you are having are still really scary!
Of course, therapy and medication may help. If you were in ERP therapy, you would probably be advised to accept the flashbacks and the triggers. When they happen, you don't react and just "ride them out" without any sort of reaction. The less attention you give them, the less power they'll have over time. If you were in CBT therapy, you would probably be advised to use grounding techniques (see, hear, taste, touch, smell) to ground you back in reality, or to distract yourself until the thoughts passed. Two very different techniques.
Personally, CBT did not help with my flashbacks or other PTSD symptoms. In fact, they made them much worse. ERP has been helpful, but I still get triggered all the time. I'm just learning to accept that I will get triggered, and when I do, I let myself feel uncomfortable because I know the threat is no longer there and my mind and body just thinks it is. When I don't have a panic attack or react, my mind is like, "Well, shit, that was no fun since she didn't get upset. Let's move on to something else."
Keep going, you'll get through this! It's a process.