18 month old with anxiety ??

Tia

Okay so obviously 18 months is very young for a toddler to have anxiety but I'm starting to think my daughter does. Whenever anyone comes over she SCREAMS the entire time and gets so worked up to where she even pukes at times. She shakes and covers her face so nobody can see her and it takes forever to calm down. I have to sit in another room with her with the door shut. It is nothing that goes on here. Me and hubby have a good marriage and whenever we do have an argument ,it is not in front of the kids. The only people who ever watches her is my mom who she loves and who lives with us and for some time she would go to the children's nursery in church. She LOVED it up until she turned like 13 months and then that stopped as she started to nit like being around other people. We have also been catching her biting her nails and finger tips a lot. Is this a normal phase or does this sound like something more?? It continues to just get worse since this all started at 13 months. It breaks my heart to see her like this and want to know if anyone else went through this with their toddler or just for some honest advice and thoughts. Thanks in advance!