Is my keg over carbed?

So I kegged my Irish Red two weeks ago. I hooked it up to the gas, set it at 30 PSI for 3 days then set it at 12 PSI. I have been testing it the last few days and I'm getting about half a glass of foam per pour. I had done some research here and today I went out and got an extra 3' of beer line, giving me 8' total. While hooking it up I noticed that in the beer line there are pockets of air bubbles. I tried serving the keg at 3 PSI and I'm still getting the same problem.

What I'm wondering is why I would be getting pockets of air bubbles in the beer line. The beer does not taste over carbed, but I don't know what else could be causing this. I had the gas shut off for a day and bled the valve every so often, but that didn't work. Should I leave it off gas longer? Or is it a problem somewhere in my line?

I get bubbles in the beer line when I overcarb. Also, I carb at 30 PSI for 2 days. 3 I find to be too much.

Finally, if you used a barbed coupler to connect your 3' to your 5', that can cause problems too. It will act as a venturi section, dropping the pressure of the beer a lot as it passes through the restriction, causing CO2 to crash out of solution. You want a single, uninterrupted line. I personally use 10', as that's what I need, but your mileage may vary.