Does the amount of water you flush through a plant affect how much fertiliser is given?

I have a few scenarios of watering with fertiliser that I've been curious about

1. Let's say I dilute some liquid fertiliser at half strength in 5L of water (for arguments sake - wouldn't really do this) and then pour all of that water over a small plant with drainage holes and let it drain until it stopped dripping. Would there be a chance of over-fertilising? (I guess I imagine whether the fertiliser kind of is absorbed by the soil/plant and whether flushing lots of water would make it absorb too much?)
2. Let's say I water a plant with regular water. If then water the plant again (allowing it to drain) with water including fertiliser, does it displace the regular water or would it get diluted more and be a weaker dose of fertiliser?
   

Thanks in advance!