Discoloured spots on my teeth?

About 2 weeks ago I have noticed on the top of both my front 2 teeth I have discolured yellowish spots that are quite sensitive to the touch. They are also slightly indented to the rest of my tooth. I brush my teeth twice a daily and have corsodyl mouthwash and have also had a healthy mouth. I have also started to notice that my tongue has a 'cracked' appearance is sore when I eat spicy food which is not normal for me. Any suggestions??