Hmmm. . . well I had a period in my teens where I had menstrual cramps so bad I'd miss three days of school each month (and I wasn't a sissy). The first time it happened, I actually thought I might be dying or having some nearly-as-calamitous medical event. So compared to that, labour cramps were much different.
In my first birth, I thought I knew all about that fear-tension-pain cycle. But really, I was overwhelmed by how painful it was and wallowed in it despite my best efforts. Certainly that compounded the pain. The pain of contractions really was sharp. I felt like I wanted to run out of my own body - like I was trapped by the pain. I tried to get out of that stupid hospital bed and change my position, but sitting upright was so painful right around the labia. (I didn't figure out until my second birth that I needed to get past fully upright and be leaning deeply forward over my thighs. Made all the difference.)
Pushing in my first birth was somewhat of a relief after struggling through labour and transition. But I did not feel in control - it was coached pushing and I remember gasping at one point, "Don't stop counting!" as the nurses trailed off. I was so in that rut of following their counting, that I just felt like everything was going crazy and I just wanted the baby to be born.
I had a significant first-degree tear in that birth and it extended ever-so-slightly into muscle (second degree). I definitely remember the searing pain of the skin tearing. The doctor said, "Don't push" and I remember thinking, "You've got to be kidding
me after 30-40 minutes of agony here!! I just want this baby OUT!"
Of course, all the lovely hormones kick in after and I felt fantastic and thought the birth went spectacularly. . . even if sit/stand transitions were pretty ginger for the first several days.
Second birth, I smartened up and I read 'Birthing from Within". I tried really hard to get into it even though some of it was a little "fruity" for me. It's a great book.
Contractions still had the intense low back pain I always get. But I could really truly feel like I was melting into them and ebbing through their waxing and waning. It was really an amazing difference. They were intense; they were consuming. But they weren't sharp or agonizing and I never had a moment of doubt that I couldn't get through all of them naturally.
I felt a distinct "ring of fire" in my second birth and thought so clearly, "Oh, that's
why they call it that!" If you get it, you'll know. (In the first birth, it was just all sharp pain that whole time and I could not discern that).
After my second, it was all pretty easy. Getting sequestered clots manually scrapped out after the birth of my twins was very uncomfortable/slightly painful, but the contractions and birth sensations were just fine. Again, "Birthing from Within" is an amazing gift to women and mandatory reading!
Great luck for your VBAC!