You will get many different ideas/answers here. I have owned my car for 10 years and have had the same symptoms several times. To solve my issues, I bled the brakes, extra good in the rear, and replaced the brake light switch and all is good. You can search for my posting on the subject and it will give you the part number for the switch.

Good luck, James

PS If the brake fluid is original, you may want to flush the old stuff out when bleeding.