Pregnancy Third trimester and pain

Hi im not ussually one to worry or tell people somethings wrong but today has been the worst. Im 30 weeks and 2 days pregnant as of today. My appointments are every 2 weeks. My last appointment with my midwife i had my glucose test. They said everything was good but i was anemic and they said i need to buy over the counter iron pills. Its been a week since that appointment and ive taken 1 iron pill a day every morning same time since they called me with the test results. On April 22 i had my baby shower i had to end up leaving my baby shower because i was overly tired and in extreme lower back pain. I litterally rushed home took a bath and honestly sat there for an hour before i could get enough strength to get out the tub. And sat with the heating pad for about an hour and a half and i felt little better. Better as in no more crying or sharp pains. Today i had to leave college early because ive thrown up 4 times and i have the upset stomach plus not to mention severe back and tummy pain again. What should i do? I want to call my midwife but they never answer the phone and jt takes hours to get a call back. I mean the baby has been moving and all. But id rather be safe than sorry. Anyone have any advice