Hi there Caitlin.
Yes you need to see a doctor specifically a dermatoilogist to distinguish between a wart
& a skin tag because that is what i suspect.
If it is the former, then yes, it may be sexually transmitted. If the latter, just a skin growth.
If you wish to be clear, please upload your photograph of the region onto this website. Should you wish discretion, then use the premier 'ask-a-specialist' feature & specifically ask for me.
I presume that as you state your mum is against the idea of pre-marital sex, you have been active. If so, please remember in the future practice safe sex
in your interests & in the interest of public safety!
Do get back to me with the visuals & will be happy to opine further & give you a treatment option.
Dr Praveen Rodrigues MD
Vikram Hospital, Bangalore, India