Is this lump a swollen lymph node or a hernia? (IN GROIN)

[JessW1988]

Hello! I'm a 30 year old female with a strange lump in the crease of my right thigh and groin (perfectly centered). It all started on a Monday when I wore a pair of underwear SPANX. I've worn this particular pair before and had zero issues; however, this day was different. After an hour or so of wearing them, they felt as if they were cutting into both sides of my groin/thigh. I kept them on and took them off around six hours later once I got home. Even after removing them, the right area was still very sore. I attempted to massage the area in hopes of rubbing out the soreness, but felt a lump instead. Instantly freaked out because I'm one of those annoying Google people, who will research until I've read every single website!!

I did notice that I couldn't seem to find the lump when lying down in bed at night.

That same week, I decided to call my OBGYN and make an appointment. The soreness had gone away by that Thursday, but the lump remained. I saw a Nurse Practitioner that next Tuesday, and she immediately said the lymph node was part of my "normal anatomy" and said it was where the SPANX had cut off the blood supply, in turn irritating both sides of the groin. I immediately felt relieved, but began researching again on Friday because the lump still hasn't gone away.

Now I'm not so sure her diagnosis was correct. She never even felt the lump because I never stood up! I was SO ready to hear positive news, that I forgot to make her check it while I was standing up!!

Everything I've read is that a swollen lymph node will not decrease in size or disappear upon lying down or resting. So, is it a hernia? I'm making an appointment with my regular doctor this week, but wondered if anyone else had experienced this or anything similar.

Thanks!