I'm new to minimalist running but haven't had any major issues in the transition, probably because I already spend a great deal of time barefoot or in flip flops.
Running in my Neos Saturday morning, I felt a sudden sharp pain in the top of my right foot above my toes. Was ~1/2 a mile from my car so I walked a bit and then ran a bit. The rest of the day I walked another 2+ miles because of some obligations I had.
I can barely walk now and have point-specific pain when I touch the top of my foot. No swelling or bruising that is noticeable.
It hurts when the ball of my foot pushes off while walking. Does not hurt when I'm just sitting or standing. When walking though, the pain radiates to my first 3 toes and hurts quite a bit. It also hurts when I flex my foot upward, but not down or side to side.
I've RIE'd(no compression) it the last two days and no ibuprofen.
Never had anything like this so what else should I do?
I currently have a stress fracture, so I've read up a lot on that. What you say sounds like it might be a stress fracture. You should definitely see a doctor. Stress fractures are kind of hard to diagnose, mine wasn't visable on the x-ray so I did a bone scintigraphy to see it. They can be hard to heal too since the foot is solicited so much. If it is and it isn't treated right it can take a long time to heal, or even never heal properly.
Also as a side note, walking barefoot DOES NOT use the same muscles or movements as running barefoot, it is not a preparation and if anything can work against you by giving you a false sense of your abilities. So hopefully you are fine, but take it slow, 5 minutes barefoot running max a few times a week, for the first few weeks, then build up slowly using the 10% rule (10% more distance per week). If you are injury prone, do two weeks 10% increase, then one week plateau. Count the 10% in terms of your overall running, but also in terms of your barefoot running. Don't forget rest days.
I wish I'd taken my own advice!