1988 Buick Century My front passenger dirrectional does not

All other blinkers work. I tried changing the bulb twice and the first time I changed it, it started to work on and off for a few days then stopped working completely. On the directional bulb itslef there are 2 lights, one that is always on and the other that blinks. The one that is always supposed to be on works. When I engage the blinker, the back blinker blinks really fast. Is this a problem I can fix on my own? I took it to a mechanic and he said it could 5 hours of labor which is very expensive.