I would like to meet with you next weekend. However, I won't go to you
because I'm sick.
I have to (jesli wymusił na mnie ktoś inny np.lekarz) lie in the bed and drink water. I have a headache and I feel bad too.
Where are you going on holiday? (jakiś plan) Have you got any plans?
If I feel better than now, we could go to the mountains. Would you like to spend time with me?
Regards.