When is a good time to go to the er?

I`m_a_mf_mermaid

I've been reading that getting leg cramps during pregnancy can be due to blood clots and I've been getting a lot of tension and aching lately. I'm trying not to be paranoid and wait for my ob appt...anyone ever have clots and can explain what it might feel like?

I have osteoarthritis and I'm a diabetic so joint and bone aching is my norm.