Bleeding after masturbating

Hi y'all. I'm 32 weeks. Used a vibrator which I haven't done in a long time. Had a small gush of bright red bleeding and 1 tiny clot immediately afterwards. Probably enough to fill half a pantyliner, maybe a tablespoon, the clot was the size of a pencil tip. It's just mild spotting now (2 hrs later). I know sex can cause spotting due to cervical irritation, but the amount seemed a little heavier than spotting?

I have a call in to my dr and am waiting for a call back, but was wondering if any of you ladies have had this experience?