Can stress/anxiety cause you to forget things? forget what you were going to say? etc...

Yes: Absolutely. Stress and the factors that may be contributing to stress (poor sleep, relationship issues, school, work problems, medications, substance abuse, lack of exercise, poor diet, etc.) can cause many problems, including the tendency to forget what you were going to say. Discuss this with a doctor and seek the help of a counselor/therapist to help decrease stress.

Yes: Stress and anxiety can do this. But there are also other causes so get checked out!