For the past few days I've suffered stomach/back. Thought it was gas; then constipation(took a laxative). Now it feels like acid reflux(took acid reducer) still have pain

That's reason enough to see a doctor and get properly treated. It could be anything from kidney's to ulcers or worse so why take a chance with people who cannot see, or test you?

If you really mean stomach (above the navel), and have pain both front and back, and it's more on your right or middle than on the left, that can be gallbladder problems.
CAN be.
Many things it could be.
If antacid worked but the pain came back, then it could just be acid, and you take another one, and another one.... and read up on all the ways to deal with acid/heartburn/reflux. I've had it for 15+ years.
If you don't have a fever, aren't doubled over in pain, aren't vomiting, then you have time to find a clinic that can accommodate your ability to pay or not, if you don't have insurance.