What you are describing does not sound like the typical rashes associated with lupus. The lupus related rash (called a butterfly rash) is on the face, a red area shaped like a butterfly across the cheeks and nose. Sometimes there is a rash on other parts of the body but it is usually a rash of red spots, or can be purplish and scaly, and appears most often on the neck, face and arms. In addition (and I'm sure you probably already know this since you have a history of lupus in your family) but other symptoms such as joint pain and chronic fatigue and light sensitivity would be present in addition to the skin symptoms.

If you are thinking that you have the type of lupus that affects the skin mainly without other symptoms (cutaneous lupus erythmatosis), you would have a circular red rash, not bumps.

I used to work for a dermatologist and there are so many different types of skin rashes, which come and go, but yours does not sound like anything serious. It could simply be an irritation due to soap or some other product you are using that your skin doesn't like, or even the dryness of the weather. The best thing to do is to make an appointment with your family doctor, or a dermatologist if you'd feel more confidence in the diagnosis of a specialist. It will put your mind at ease.