Jonknee

Car: ef sedan
Engine: d15b

Having a small problem here I just had a small coolant leak on my headgasket so I went and replaced with a felpro 3 layer headgasket, milled the head 15 thousands and, put head back on with new sealts and what not. To set my timing i Put the pulley tdc mark matched with the timing belt cover notch, and put my stock cam gear matched with the top of the head, put back the timing belt, feels a little looser now. I then started the car and noticed it runs ok* idles at 900* and the idle will go down after 2 minutes of running and it will just die.
There is like 4 little brown bubbles that i can see through the radiater fill hole but i think thats leftover coolant from when i took off the head and coolant spilled on the block.

Summary:::::
Could a headgasket cause the idle to die like that?
Could bad timing cause it to die like that?
Should i get off my *** and buy a cam gear?
Ecu throws no codes at alllll.
If i rev the car it will rev like normal.
no unusual noise sounds the same.
IT smells more like gas now. strong exhaust smelll