528iDude

so i got some ddm lows and fogs
the lows are 55w and usually always turn on when i first turn the dial over.
but the fog lights do NOT turn on when i press the fog light button.
Forcing me to turn off all my lights and doing everything again.

Soon the low beams will start flickering when i keep turning the lights on and off and eventually turn off.

i have a few questions:
-do i need a error decoder for my 55w set up? (i thought error decoders were only for 35w kits?)
-do i need a relay for fogs? - or are there alternatives? (
if i do need a relay, what kind of relay? or will any ebay relay do the job? (i dont want my car to catch on fire due to electrical stuff)

Note: i have a 2008 528i lci halogen. Error decoders on my fogs.

sorry for all the noob questions.
but any replies would be awesome and helpful!