Yes, it is my understanding that if one of the blinker bulbs blows out or isn't seated properly, it will blink at a quicker rate. This happens on my truck as well. Good luck and let us know how it turns out for ya.
This is pretty normal for most vehicles that use incandescent turn signals. The blinker is an electro-mechanical heat switch. The current draw of the two lit bulbs heats a strip and it bends and breaks the circuit, then cools and closes the circuit. If a bulb is burned out, there is only half the load/heat, and it will change the blink rate.
LED lights pull so little power they are incompatible with electro-mechanical heat switches. So if one REPLACES a bulb with an LED one has to use a load resistor or change out the blinker for a fully electronic one. But typically you can add ADDITIONAL turn signal LED bulbs to a dual-incandescent system and it will not change the blink rate.