Be silent
The more we talk about sex, the more often it becomes clear that the participants in the process may have almost diametrically opposed views on what has already happened.
Criticize
Yes, forbidden phrases are evil, but criticism in bed means a disdainful, harsh and rude tone. If something does not suit you, you want to stop the process, you realized that you missed the orgasm, you have a stiff leg - tell about it directly.
Perhaps, the partner will be upset and ask what is wrong with what he does. You'll have to be patient and sound that he is not guilty of anything, it's just that your leg is stuck and orgasm is gone. You are ready to continue this way and so or help your partner to finish, but in your side of the gestures you no longer want
Do not pay attention to pain
If you are hurt at some kind of action - do not be patient. Tell the partner about it. If you are hurt only by penetrating sex, but in general you want to continue - you have a huge number of options for another interaction.
Pain is an abnormal reaction. Try with the help of a doctor to find out its cause.