I had a case that was almost similar....my daughter in law.
First baby, 18 y/o. BPs in the 110/70 range through out pregnancy. She and my son were living with me so I was monitoring her diet, which improved greatly after moving in with me. She woke me up at 8:30 am, complaining of "cramping". Listen to baby, take bp, 110/70, and contractions seem mild so I suggested she go back to bed and try to sleep. I made coffee, checked on her, she was sound asleep at 9 am, snoring, even. At 9:20 I hear her hollering for me, says she feels like pushing, and sure enough, she's complete and +2! baby born at 9:46! Lovely little boy....take BP about 30 minutes PP, it's 138/86...ok, super fast, intense labour, give her a minute to recover. Baby nurses, placenta delivered, mod blood loss. She says she feels like she's getting a headache..take BP again.....150/98.....no clonus, no swelling, no back or epigastric pain. 1 1/2 hours pp recheck and good lord it's 180/100! Call my back up, bring her in, by the time we get there (20 minutes) her bp is 210/112! She gets admitted to CICU, put on mag sulfate and another medication that I forget but it was a cardiac med, liver enzymes all over the place. She didn't seize (I don't know HOW she didn't have a seizure with those BPs!) Anyway, she ended up staying on CICU for 8 days while they tried to get her BP under control. She was able to pump a wee bit of colostrum and milk when it came in, but the baby was mostlry formula fed for those 8 days. We were all a bit worried she wouldn't be able to nurse, but when she came home and held him, she began dripping milk. she put him to breast and he latched like a champ...and we threw out the formula when it was clear she had a great supply and he is still nursing at 2 1/2 years.
I think her baby knew it was about to blow and that's why she had such a fast labour.....get the baby out NOW sort of labour. Her BPs remained high (140/80 range) and she was on medication for about 2 months after the birth when she was able to wean off them and they have remained stable (and normal) since. She is NOT trying to have another baby anytime soon.....she was freaked out by how quickly she got sick afterwards.