Lower back pain is not the only indicator of sciatic nerve pain. This kind of pain generates in the lower back and is felt traveling through the buttox and down the large sciatic nerve in the back of leg. For most people, this gets better with time, usually a few weeks or months. Please know that sciatica is a symptom of a problem, and that something is pressing or irritating the nerve. You very well may need treatment to relieve the problem causing the pain. In the meantime you can take ibuprofen which is an analgesic/anti-inflammatory, to help with the pain. You can alternate applying heat packs and ice packs to the area for only 20 minutes every hour and see which feels better.
The websit below demonstrates execises to relieve sciatica.
You must visit the doctor for a definitive diagnosis.
I hope all will be well with you!
I understand it is very expensive without medical insurance, but I am wondering if you have a bulging disc and that is what is causing the pain. Rest is very important and anti-inflammatories will be helpful. I am concerned about you encouraging more damage by not being evaluated and treated. Some back problems resolve on their own and some need medical or even surgical treatment. Is it possible to go to a local chiropractor for an x-ray and some treatment. Some of them will work with you for a reduced amount if you explain. I really think you need a proper diagnosis. You can do the treatments I recommended, in the meantime.
A bulging disc can be anywhere along the spinal column. If the lower back were affected then the pain could be referred to you buttox and even your leg. You also could have strained your butt muscle. But you said that your back hurt when you bend over. You can take the ibuprofen and alternate the ice packs and heat packs for comfort at this time. And of course rest it and put no strain if possible. This is the best that you can do without a definite diagnosis. Perhaps someone can massage the area for you as well.
I will be away from the computer for about an hour and will help you then.