Really bad muscle spasms in my lower back. Can I use one of those stickon warm pad things from walgreens?

Give it a try. Warm compresses to help relax muscle spasms are some times efffective along with a nice warm jacuzzi. Also massage and light muscle stretching exercises can be helpful for prevention and treatment. If pain persists then see your physician for possible Flexeril (cyclobenzaprine hcl) or other muscle spasm treatments.