Re: Can semen leak from base of condom during sex?
As long as you had the condom on properly, (with the end free to hold the semen at the tip), there is no reason for the semen to leak out at the top. There should not be enough room for the semen to get squeezed that far up, as long as the receptacle was free to hold it. Was the condom in place all the way up the shaft when you were done? It was not rolled down, for example.
Any white fluid you see on your gf is likely one of the things you mentioned...lubricant, her own fluids, etc.
You should be safe if all was in order with the condom placement when you were done.