Hi P. - If the school counselor has suggested this then the district will need to start the special education process of evaluations (don't be scared by the term special ed, this covers so many more kids than we realize). Schools can not give a "diagnosis" (they can guess all they like but dont take it to the bank unless you have outside expert work with your child to verify - save money and let the school do the evaluations, then you can take those with an outside expert - developmental peditrician, etc). Just so you know even if your daughter does get some ADHD, etc diagnosis that does not mean they automatically give them medication, majority of the time these kids function right along with typical peers but with some accommodations, classes, tools, etc that help them the best way they individually learn.
Since you are starting a new venture of the schools you will also have to help educate yourself about you & your daughter's rights. One of the other posters already suggested www.wrightslaw.com and I can't tell you enough that is one of the best places to start learning about this process. One thing to also understand is that kids may have all types of disabilities but for them to qualify for special ed services their evaluation testing has to fall under a set % (this you will be able to learn via Wrightslaw). Start now and document any conversations, letters, etc with the schools or specialist (use a notebook, like a journal), this will help with any documentation if needed but it will also allow you a place to write about your daughters behavior and other observations that will help when working with professionals. I was glad for mine because it also gave me a place to get my frustration out when dealing with our district. If for some reason your daughter does not "qualify" for special ed services (IEP) she very well may have rights & accommodations under the Section 504.
Special Education & Learning Disabilities is such a large category of what it can include. I also suggest that you go to your state's department of education website and they "should" have their state special education manual, this will tell you just about everything that you will need to know about the process and the % for qualifying. Also check to see if there is a parent support group in your area, they will be a wonderful place to get information about specialists, doctors, etc as well as offer support about this possible change in your life.
I am sure this will all start to feel overwhelming but know that you are not alone, just take it one step at a time. Connect in person with other parents as well as online will help you with your support structure. One day at a time! God Bless