to Islam and not married and you want to perform Hajj or Umrah - do you need a mehram? And who would that be for you?
Re: If are a convert....
Peace njgal
It is advisable for a woman not to go to Hajj in such a situation. Hajj is not obligatory on such a person. When a person has the means to go to Hajj then they should go. For a man this is to be post-pubescent, sane, rich enough to go and debtors cleared or informed/permission sought and if a woman all this plus the ability to travel with a mahram.
If no mahram then Hajj is not required, rather advised against.
Re: If are a convert....
Peace Njgal!
i'll quote here a hadith. rest as psyah said. :)
Sahih Bukhari Book Penalty of Hunting While on Pilgrimmage
Hadith No. 85
*Narrated Ibn 'Abbas: The Prophet said, "A woman should not travel except with a Dhu-Mahram (her husband or a man with whom that woman cannot marry at all according to the Islamic Jurisprudence), and no man may visit her except in the presence of a Dhu-Mahram." A man got up and said, "O Allah's Apostle! I intend to go to such and such an army and my wife wants to perform Hajj." The Prophet said (to him), "Go along with her (to Hajj)." *