I'll attempt to summarize again: This seems to be Thistle and Sensei picking up where the last manga left off, in their daily routine of developing and testing rapid-faux-pregnancy meds. Sensei decides to immediately test the newest one, despite feeling under the weather -- though I've no idea if she's feeling period cramps, caught a flu, or is just worn out from a prior experiment. After spending a couple hours to recuperate she hooks herself up to the IV and asks Thistle what she settled on for the dosage, who I *think* replies, "I figured it'd be the same as our usual experiments, so I doubled it." This one apparently takes a couple hours to kick in, so Sensei decides to take a nap and tells Thistle to go get herself dinner and come back in a two hours. Then there's an ominous shot of her leaving at the top-left of page 5 which is probably supposed to mean she upped the dosage more than she said. They seem to enjoy testing their limits with this stuff, after all.
Sensei wakes up sometime later, immediately realizes something is wrong when she can't move under the weight of her own belly, thinks to herself, "There must've been something wrong with the dosage, but since I've blown up this big it must be empty... HALFWAY!? This is getting dangerous!"
Thistle comes back and just kind of panics, Sensei expresses multiple times how close she is to bursting while having a wild orgasmic egg laying session trying to outpace the rate at which she's growing, and I'm unsure if they just kind of forget about the remaining half of the IV while this is happening.
Page 12 is something along the lines of: "If you up the dosage, you need to keep a close eye on the subject in case something like this happens. I'm glad it was me, but seriously, if there had been even a few more eggs in me I'd have split open. It's good to be curious, but that being said... ...Here, take this." "What's this?" "It's the other experiments I was going to run today. I want you to do it for me. Eight times." "EIGHT!?"