Hallow,
Just go through the bellow act. Your matter covered the bold portion of the act. Normally you cannot marry under the hma, but if you marry, enjoy the marriage and thereafter try to get escaped from the marriage responsibilities on saying that as you are not a Hindu therefore HMA has no power to attract the marriage, then you will understand the power of HMA by virtue of sec 2(3) of the act. Though you are not a Hindu but by virtue of sec 2 (3) you will be attracted under HMA as the marriage already solemnized under the Hindu marriage act.
In a marriage only spouses are concerned. No other can interfere into it. If both the spouses changed their religion the personal law changed accordingly. But if there is a difference of opinion or divorce situation comes, then the whole matter comes into lime light. Though sec (a) & (c) refuses the marriage but sec 2(3) attracts your marriage.
It is a theoretical question that, what will be the position of your first marriage, if you gone through another marriage, under another marriage act, which one will be active first or second?
Are you refused by the register of Hindu marriages? Then what is the use of another marriage?
Final decision is your’s, but think before you done. One wrong step cannot be washed by another wrong step.
HMA SEC 2. Application of Act.
(1) This Act applies-
(a) to any person who is a Hindu by religion in any of its forms or developments, including a Virashaiva, a Lingayat or a follower of the Brahmo, Prarthana or Arya Samaj,
(b) to any person who is a Buddhist, Jaina or Sikh by religion, and
(c) to any other person domiciled in the territories to which this Act extends who is not a Muslim, Christian, Parsi or Jew by religion, unless it is proved that any such person would not have been governed by the Hindu law or by any custom or usage as part of that law in respect of any of the matters dealt with herein if this Act had not been passed.
Explanation.-The following persons are Hindus, Buddhists, Jainas or Sikhs by religion, as the case may be:-
(a) any child, legitimate or illegitimate, both of whose parents are Hindus, Buddhists, Jains or Sikhs by religion;
(b) any child, legitimate or illegitimate, one of whose parents is Hindu, Buddhist, Jaina or Sikh by religion and who is brought up as a member of the tribe, community, group or family to which such parent belongs or belonged ; and
(c) any person who is a convert or reconvert to the Hindu, Buddhist, Jaina or Sikh religion.
(2) Notwithstanding anything contained in sub-section (1), nothing contained in this Act shall apply to the members of any Scheduled Tribe within the meaning of clause (25) of article 366 of the Constitution unless the Central Government, by notification in the Official Gazette, otherwise directs.
(3) The expression "Hindu" in any portion of this Act shall be construed as if it included a person who, though not a Hindu by religion, is, nevertheless, a person to whom this Act applies by virtue of the provisions contained in this section.