If there is a concern it's brilliant to get assessment started so soon, that will mean you daughter has the best possible support. If there isn't then you will have put your mind at rest.
Genetic tests are standard for autistic children as some conditions mimic the effects of autism so they like to rule them out early on. Ours were done at the hospital were they have a very good set up for dealing with young children and do everything possible to help them feel relaxed.
With regard to diagnosing your daughter they probably wont right now, they will put 'autistic traits' or something and refer her to a paediatrician. They paediatrician will see her every six months or so and slowly decide if there is anything to be concerned about. In the mean time they may recommend things like Portage or speech and language support if they feel it's appropriate.
My sons are both autistic. The were initially diagnosed with global developmental delay with autistic traits about your daughter's age then formally diagnosed at two. They have received ongoing support from the paediatrician and their diagnosis has been clarified over time. It is a an ongoing process not a one appointment thing.
Try not to worry to much, you can always message if me you have any questions. If it's an reassurance to you my sons are currently five and eight and got to a fantastic special needs school. They have had opportunities I could never have offered them and are in small classes getting close to one to one support from staff. Their teachers are brilliant and identifying their skills and encouraging them to reach their full potential.
Life can be more challenging at times but I wouldn't change a thing. Nothing about the diagnosis changed who your daughter is, she is just the same. If she is autistic you have just learnt something new about her and will have lots of help in finding the best ways to support her so she can reach her full potential.