Contractions or BH at 23 weeks?

So I'm around 23+3 now and got my emergency cerclage at 19 weeks. I don't know my exact length now as my doctors won't do a transvaginal u/s after the cerclage. Their idea is to not disturb the cervix at all(which I kinda agree with) but they did tell me that I'm approximately 1 cm. I am also taking 1 nifedepine/procardia in the morning along with labetalol for hypertension. Around a week back , last Friday I think, I was having contractions every half an hour. Also accompanied by period like cramping.

Since the nurses told me that nifedepine is a drug to stop contractions, I took an extra dose that night and I didn't get too many 'contractions' (or BH) since then. I am unsure if these are contractions or Braxton Hicks. What happens is that my lower abdomen tightens up. I can feel it but on touching my stomach is still squishy.

My doctor has told me to continue with my daily morning nifedepine dose and to only take an extra one as needed.

Wondering what others experience has been regarding this? Are you guys also taking it on sos basis or what? Will I build up tolerance to it and it will stop working?

My baby is so close to viability that im really scared of losing her now 😢