Yup. I personally think that the SI is worried about his lack of reaction over his decision to go full Plague Inc. The later is easily explained away as the SI jumping the gun due to trauma and stress, the former is much more serious.
Nausea's function is to keep organisms from eating rotten/poisoned/diseased things, or eating near those, thus preventing possible infection. The usual reaction of fear and disgust of humans from seeing their kin splattered all over the walls and ceiling is to keep the human well away from the stomping grounds of the thing that did that, be it a disease or a creature. It's the instincts telling you: something fucked up those like you here, it's unlikely to make an exception for you, get the fuck out of dodge now. Also as pack animals, humans tend to have some measure of empathy as default, at least enough to learn from the fuck-ups of others and to keep them from killing each other most of the time, both of those increasing their odds of survival as a species.
To have no visceral reaction to that kind of extreme gore means the SI's wiring is all kinds of fucked up, he doesn't recognise humans as kin subconsciously anymore, after all, how much of it is from the trauma (mish-mash of memories included) and how much from the completely different brain chemistry is anyone's guess. But he is notably less human than he started up as (change of body notwithstanding), which worries him.
On a sidenote, most have such reactions to bioweapons due to how indiscriminate they are, and how easily they can slip out of control. Radiation is easy enough to predict and detect, only taking some competent physics and climatologists to chart out its spread. Diseases are an absolute bitch to contain, with incubation phases, easily mistaken symptoms, resistance bodies able to withstand decades until the environment turns favorable again, mutation and exponential growth. It doesn't help that certain bacteria can incorporate genetic material that's just floating around, or exchange genes with other bacteria, or that most viruses can be tricked into putting just about any genetic code into their capsules while they are being assembled in the host cell.
