Here's The Timeline...Thursday Watery Stool. Friday Watery Stool Often. Saturday

Here's the timeline...Thursday watery stool. Friday watery stool often. Saturday watery stool with suspected blood. Having to go less and less. Sunday first stool very small, watery and red. All day after that no stool at all. I am drinking extra water and eating normal but no stool. Eating normal. Taking naps Friday thru sunday. I took Imodium as prescribed by the box Thursday, thru Saturday . Sunday afternoon started lower back pain. Seeing doc tomorrow. Thoughts?