Fuses blow when the current in the circuit exceeds the fuse rating. That happens most commonly due to a short to ground. A wire gets crushed or abraded and the conductor touches a grounded part. A short may also happen in dual filament bulbs (1157s, for example) when the filaments may short to each other, or the bulb socket is corroded. Do all of your turn signals and brake and parking lights work properly now??
I'll venture to say that if the only thing you did to "fix" the blown fuse was to replace it, I hope you bought at least two of 'em.
Replacing the blown fuse didn't repair the short, just covered up the problem 'til the next time. I would inspect all the bulb sockets and wiring at the fixtures. Clean the terminals in the sockets and the bulb bases and check the ground leads and their attaching points.BC