Overheated a couple weeks ago I added coolant to radiator and seemed fine but was hearing a bubblig noise occasionally. Yesturday it started t get very hot again and the noise seemed much louder the evening before.
What is the problem?

 

What does the temperature gauge read? Is it in the middle or above the middle line?

 

when overheating it goes above the mid line the first time it got close to the end of the red markings. This time inbetween the mid line and the very top red line. Hope that makes sense.