Late period

Sooo I am now 2 days late on my period, and have never been late in my entire life. Have had safe sex this past month, and have been exercising more and lost some weight. I'm assuming the fitness and weight loss are the reasons, but I'm freaking out right now. If anyone has some insight or tips to induce your period please let me know because I'm 20 and cannot have a child with my 19 year old boyfriend.