Welcome to the forum Sarah
I do hope this consultant's suggestion marks the beginning of better health for you. Diagnosis and testing are fully outlined on the Information section of this site
www.thelupussite.com.
The ACR Criteria mentioned already were not meant for diagnosis but they are a good guide of features of SLE that are considered typical of lupus. The so- called Alternative Criteria are very interesting - they aren't exactly used except in tricky cases by lupus specialists as additional clues to diagnosis.
Some cases of lupus are hard to diagnose because it is a very complex disease with a huge variety of presentations and atypical cases. There are often overlap conditions too, either other autoimmune connective tissue diseases or other conditions, whether autoimmune or not.
I hope you turn out to be one of those doddle cases but you need to be aware that diagnosing can be a lengthy business and might involve other specialists too, such as a dermatologist.
Your GP should be willing to do tests such as ANA and RF as well of course as a complete blood count that could show significant abnormalities.
If you have any questions about the info just ask us.
Do you now need referral to a rheumatologist ? I suggest you ask here about lupus specialists in your area.
You can start by preparing your health history leaving nothing out except possibly mental health issues unless they are current and you are on meds.
Then make a list of more recent/current chronic health issues and a note of chronic health issues of close blood relatives - diabetes thyroid cardiac miscarriages rheumatoid arthritis kidney disease for example - all might be relevant. Also note of medicines you have been taking in recent years.
Keep in touch and let us know how you get on !
All the best
Clare