I Have Been Having Severe Bloating In My Belly For

i have been having severe bloating in my belly for 3 days with constipation, yesterday I started having shooting pains up into my rectum when I sit down or get up. I have taken laxatives ate burns with hot coffee.
today I had diahrea sp and I thought I was headed for relief, not. My stomach is still destined with pain in lower abdomen and the shooting breathtaking pain up into my rectum should I take miralax or go to hospital. I'm a 60 year old woman in reasonably good health.