I think it might just be tuned really high....loosen the string slowly and go down from E to Eb to D....till you get to B. In case you're really new and don't know how to tune a guitar, just go on youtube and search for "how to tune my guitar" and I'm sure it'll come up with something.
All done but wen m lowering the string its going v. low with B & wen i higher it a little its going E :\
that doesn't sound right....I really don't know what to say to that. Just to be sure, this IS a guitar we're talking about right? I've seen what you're saying happen with an ukelele.
It could also be that your tuner is not of good quality. Cheap tuners tend to pick up a related note(harmonic) of the note you are actually tuning to for some strings due to poor design (internal resonance). This can be identified when the note displayed on the tuner drops drastically when you change the tuning by about half a note. This would usually happen for only 1 or 2 strings at the max. So if you have the other strings tuned, bring the string in question to approximate tune(using 4th/5th fret of the lower string to tune the higher one). Then get it to exact tune for the note it is closest to on the tuner.
this also happens when your B or 2nd strings is tuned 1 octave lower to the higher E..lets say the 1st string is tuned in E2 and the 2nd string is tuned to E1 both are E note both different octaves...but the tuner will show E only...so if its tuned in E1 then definately if you want to loosen the string in order to get B note ...then the string will become too slackened and you wont get a well pronounced tone out of the string...