found a pea-sized lump in vaginal canal

Hi, 

I'm 20 and I recently found a pea-sized lump like 2-3 inches within my vaginal canal. It doesn't hurt or anything and it's in the middle of my back wall if that makes sense??  But I brought it up to my boyfriend because I'm a bit of a hypocondriac and he said that he thought I knew and that he's been able to feel it since begginning of January. I'm freaking out what it could be, please help?? I have a doctors appointment on the 6th of March because my blood tests have come back abnormal (this is related to maybe having a food allergy). I know I am probably overthinking but any advice  would be appreciated!!! Thankyou in advance x