I feel so exploited/that the system is exploitative being asked to do an extra hour

Hi all

I am currently volunteering in a school in Kyrgyzstan. I'm from the UK so it has been a pretty massive ajustment for me and I am here for a months, and have been teaching in the school for the last 4 days. On average, I am only doing 3-4 hours a day (9-12, or 9-13). It's a work away style scheme, so I am given accommodation with a host family as compensation for the work. Background context is that I am running an extra speaking club so that the children can practice speaking English with me.

I have been finding it extremely difficult to adjuct to life here. I have just gone long distance with my partner (and will not see him until January. He is also moving to Brazil and I am moving to Kazakhstan after this month so it's going to be difficult) as well as the huge culture shock and never really being this independently alone as a 20 year old woman. This all means I've been sleeping like asss so find myself exhausted by the time 12 comes around and I get to leave (also not to mention I am doing half of everything in Russian which is a language I haven't been learning for very long).

Now, I want to know the experience of other people here: I feel really opposed to what one of the owners of the school has asked of me - that I come in for 8am and do an extra hour before and then possibly the extra hour after (also keep in mind that they don't tell me much, I get little notice. Today I had 30m notice that I was going to have to stay until 1, not 12). I don't really want to have to go in for 8am, wake up an hour earlier to make the commute, and be teaching these people on 4h of sleep. That just feels like a diservice to them, their time, and the money they are paying for the school.

The tricky thing is that it feels to me that it should be roughly even - I do as much work as would cover accommodation as well as the inconvenicence and hospitality required of having someone else in your home. Naturally, it would never end up that way, and so I am happy doing the 15 hours a week minimum and doing the few extra substitution lessons here and there. I also want to add that I know I have it easy haha. I am working 0 hours compared to the other people on this sub/in the real working world, but it feels very difficult when I am not really recieving compensation in the form of money (it feels different when its accom).

The other thing is that the whole system feels messed up to me. I am being asked to cover a lesson at 8am every Friday because one of the full-time teachers really can't be bothered (trust me, she really can't be, and she already does nothing). I really don't like the idea that I, an unqualified and inexperienced person, is covering lessons that people are paying for. I don't think I am in any way good enough for that, just so this person can skip an hour and chill. I don't want these people to be missing out on quality teaching. There is also the fact that the techer would still be getting paid for this hour but I won't be, but that doesn't make me as uncomfortable as the fact that I am inexperienced.

I am so so on the fence. It is ONLY an extra hour, but it with all of the other factors it just feels like it stands for a lot more than that. But then again, I am young and have no experience with this stuff so I am maybe just overthinking it.

Can people please let me know their opinions on this/advice?