Contractions getting intense but not closer together

have gotten more intense but they don't seem to be getting closer together they are between 6 up to 15 mins apart but I've had them like this since yesterday afternoon and they haven't stopped. The pain feels like someone is squeezing my guts to death and I'm struggling to breath through them. I rang hospital and they said to wait until they are 3 mins apart but I'm worried as they seem to be getting intense but not closer together.