If the FIR is got registered in the high court so u also need to appoint an advocate on your behalf so that the girl proved wrong and better if u ask the court to get medical test so that u cannot be found guilty after proving that girl wrong you can also lodge a FIR for Defamation under section 499 of IPC.
Section 499 in The Indian Penal Code
499. Defamation.—Whoever, by words either spoken or intended to be read, or by signs or by visible representations, makes or publishes any imputation concerning any person intending to harm, or knowing or having reason to believe that such imputation will harm, the reputation of such person, is said, except in the cases hereinafter expected, to defame that person. Explanation 1.—It may amount to defamation to impute anything to a deceased person, if the imputation would harm the reputation of that person if living, and is intended to be hurtful to the feelings of his family or other near relatives. Explanation 2.—It may amount to defamation to make an imputation concerning a company or an association or collection of persons as such. Explanation 3.—An imputation in the form of an alternative or expressed ironically, may amount to defamation. Explanation 4.—No imputation is said to harm a person’s reputation, unless that imputation directly or indirectly, in the estimation of others, lowers the moral or intellectual character of that person, or lowers the character of that person in respect of his caste or of his calling, or lowers the credit of that person, or causes it to be believed that the body of that person is in a loathsome state, or in a state generally considered as disgraceful. Illustrations