Time wouldn't have been an issue, the TARDIS is a time machine after all. The food thing is more of a problem, as is the damage to whatever planet's eco system she chose (also, would the spiders keep growing once removed from that environment? I don't recall if that was addressed)
This is two consecutive episodes now where the doctor has had to stand back and allow something awful to take it's own course, a valuable story telling tool and possible underlying message but hopefully we'll see her being a little more proactive as well.
One thing that did strike me a jarring though was the objection to Donald Trump killing the mother spider. The anti gun/pacifist message seemed diluted to me given that his actions amounted to an unintentional mercy killing at that point, she was dying painfully and he shortened it. That wasn't his intent by any stretch but he was given the self awareness to comment on the fact where the doctor seemed pretty inflexible, preferring to let her suffer than play a direct role.
This is two consecutive episodes now where the doctor has had to stand back and allow something awful to take it's own course, a valuable story telling tool and possible underlying message but hopefully we'll see her being a little more proactive as well.
One thing that did strike me a jarring though was the objection to Donald Trump killing the mother spider. The anti gun/pacifist message seemed diluted to me given that his actions amounted to an unintentional mercy killing at that point, she was dying painfully and he shortened it. That wasn't his intent by any stretch but he was given the self awareness to comment on the fact where the doctor seemed pretty inflexible, preferring to let her suffer than play a direct role.