Can You Fast without Ghusl?
Question

I once had a wet dream just before sehri... it was not possiblt for me to go and perform ghusl rather.. i felt very shameful to go to perform ghusl... since my parents wud cum to know... so i had my sehri without performing ghusl and tha't morning unfortunately i even didn't pray fajr prayers... but later... i performed ghusl and i parayed by fajr prayers... but i wud like to know whether my fast is valid... 'cuz i think i went wrong here becuz i had my sehri in a sexually impure form.... Is my fast valid?
Praise be to Allah.Can you fast without ghusl?
The fast of one who has intercourse with his wife at night and wakes up in the morning in a state of janabah (major ritual impurity) is still valid, as is the fast of one who becomes junub in his sleep, whether at night or during the day. 
There is nothing wrong with delaying ghusl until just before dawn. Rather fasting is invalidated by having intercourse during the day in Ramadan, from the onset of true dawn until the sun sets. (Fatawa al-Lajnah al-Daimah, 10/327)
Delaying prayer because of feeling shy to perform ghusl
With regard to your delaying the prayer until the sun had risen, this was wrong of you to do that. What is obligatory is to perform the prayers on time. Feeling too embarrassed to do ghusl is no excuse for delaying the prayer. You have to repent from that and pray for forgiveness.
May Allah help us and you to do all that is good.
And Allah knows best.