My language exchange partners is sick. I hope she gets better soon.

She said:
I can't believe I got sick two Saturdays in a row. This week, I don't think I am well enough to practice. I am sad to miss out on our session. Can we please come back next week? Thanks!

My reply:
Oh, it's too bad to hear that! Please drink more water and sleep more. Wish you can get better soon. See you next Saturday. Hope you will have a full recovery at then.

Hope these corrections help. Getting sick two Saturdays in a row, poor girl! Hopes she feels better.

She said:
I can't believe I got sick two Saturdays in a row. This week, I don't think I and am well enough to practice. I am feel sad to missing out on our session (actually, I'm not sure bout this one). Can we please come back meet each other next week, please? Thanks!

My reply:
Oh, it's too (in this specific context I would prefer to use so, but it's not that wrong tho ^^) bad to hear that! Please (no need to use this, but if you want - put it in the end of the sentence) drink more water and sleep more well. Wish you can get better soon. See you next Saturday. Hope you will have a full recovery at by then.