While this does sound somewhat similar to my leak, to be honest I think you are probably OK. For me, my erections remained a semi, or subsided after like 5 seconds, and I could not even kegel blood into the head since blood was leaking out so fast - it felt like the kegel ‘muscle’ was completely disconnected from the head of my dick.
Even post surgery, if I’ve masturbated once or twice in a day the erection can subside after around 15 - 20 seconds, and at first the head doesn’t fill up all the way, the shaft tends to fill up first….. and the head can inflate as I kegel then slightly deflate. This, however is normal in my opinion. With a girl I’m comfortable with it generally stays full and hard. Even after surgery I had some trouble with erections, but it was primarily psycholigcal since the problem had completely consumed me. A few weeks off the computer, the right girl & not thinking about it helped A LOT.