On a low dose and for only 2 months, there's probably enough to work with to bank. Don't leave it too long. If the count is too low, if you really want to bank, then you might have to go off HRT for a few months before trying again.
It took me about 18 months before I was effectively sterile on low dose, but it's not something I've been specifically keeping an eye on.
Of course, please talk to your Doctor - that will be your best bet.