How to stop infatuation and concentrate?

Due to health reasons I had to meet a physiotherapist and she treated me for 10 days(this happened 7 months back).She is 14 years elder than me and married.And now I am receiving treatment from an Occupational Therapist and she is 8 years older than me.I came to know my physio went to some other place but I want to meet her.My head is filled with thoughts of these two.Seems like I am infatuated with them and I am not able to concentrate on my studies.I feel like I want to see them everyday.I'm a teenager.Is this common in teenagers and how do I handle this situation?Should I stop seeing my OT also?How long will this infatuation last?