Hi,
It’s tough to be without your partner - the second night can be a very lonely night. And it sounds like you are worried that the trauma of your first breastfeeding experience will play out again. After giving birth so recently I am betting it’s not just your boobs that are tender and achy, I’m betting the rest of you pretty much is too. What makes you think the blood pressure meds are affecting your supply? Is your baby feeding at the breast? 1.2 mls seems a pretty normal amount to express at this stage. A full feed would only be 5 or so mls.
Call a midwife - get some help and reassurance. Or call the ABA 24hour line. You don’t have to breastfeed - but if you do you have every chance if that’s what you want - thanks for posting on Belly Belly, its best not to suffer alone.