basking = healthy turtle?

Question
QUESTION: I recently acquired a yellow belied slider. It's quite young, not sure of age but it's about 1 1/2 inches. When basking he sits on the ramp up to the basking area, submerged completely, apart from his head. I know this is bad because they need to get completely dry every day to stop them from getting infection. I'm planning on bringing it to a vet but I don't know of any near me that will look at turtles.
Anyway, I've noticed that the turtle has a grey-white mark on it's top shell. What does this mean?
Also, when I had it out of its tank today I noticed that it seemed that the turtle's backbone was protruding from it's top shell, if that makes sense? I thought it could be a symptom of soft shell, but this is my first turtle and the only information I have to go by is that of inconsistent nature on the Internet.

ANSWER: This is a hatchling so it sounds.
spot on its shell sounds like it can be an onset of fungus.
what type of enclosure is it in,
are you using heat and uvb
is it ever outdoors

it is ok that he is basking and leaves his head out and as long as he is able to get out,he will if he wants to.

If you tell me your general city and state Ill find you  a herp vet.

---------- FOLLOW-UP ----------

QUESTION: it's in a glass tank, 11" by 23" and about 10" of water. Capacity is around 60 litres. I have a heater keeping water temp at 27 degrees Celsius and a strong filter. Light is about 4 inches from water, is this too close? And no, it's never outdoors.

Also, I'm from Northern Ireland, Co. Fermanagh, Enniskillen.

Answer
Hello, these turtles are born outdoors with the natural sun to aid in the hatching. They need uvb fro the sun to grow properly, digest foods, etc. If you do not provide the correct sun and care he will suffer. He can not go out in the tank. Glass tanks do not release heat. It will slowly kill him.
You can reduce the amt of water. as long as it is 3 times the legnth of the turtle so if he is alost 6 inches give him 6 inches. then he doesnt get scared, tired etc.
this will reduce sress as well./