I need help please help!!?

My sister brang her friend over and her family been infested with bed bugs i believe,and ever since she had came over i felt really really itchy. has lil things r jumpin on my skin & walkin up n down movin n bitin my skin, I had all my belongings washed/put outside 2 dry opened all the windows and brought an diseffive spray and sprayed the beddings n carpets..if anything it made it a little worster i opened all the windows i felt a little relift.. I also felt vary itchy in the car on the way droping her Off home..I feel vary itchy right now I really dont no what to do anymore and vary annoyed with this.what can i do please help,I really don't have alotta money too Buy expensise products please help thanks..