Braxton Hicks + vena cava compression?

[Dill]

I'm currently 25w4d. I've been experiencing terrible chest pain (tightness in my chest and back) accompanied by dizziness and difficulty breathing. It's been occurring with increasing frequency over the last few weeks. I brought it up with my midwife at today's appointment, and she believes it may actually be braxton-hicks contractions that are pushing the baby up against my vena cava. I'm supposed to keep a journal over the next few weeks to track when it's happening, what I'm doing when it occurs, my heart activity, if my abdomen hardens, etc.

Has anyone else encountered this issue?