You can over do potassium, but most people don't. If you eat a banana, potato, or have orange juice, this should be nearly sufficient for your daily intake. Broccoli is also high in potassium. Like in the other response you have, those amounts of potassium will make you sick. It you feel like you have a queasy stomach, then you can drink the juice, or eat a potato or eat the banana, and you will lose that feeling of wanting to get sick. Hope this helps, good luck to you.
Actually, bananas only provide about 10% of your RDI (reccomended daily intake) for potassium.
My sister had a phase where all she ate was bananas. Everyday she would have a couple bananas for breakfast, lunch, and dinner. After a while she got a headache, got sluggish, and was pretty sick with a fever and all. She cured after a while but my mom and dad kept her on a limit with bananas. (Oh yeah and bananas have a lot of Potassium).
I have started taking lasix for swelling and a potassium supplement. But I have also been very sick throwing up, could that be from the lasix or the potassium