When did you get an actual period?

I was on the pill for about 5 months from December to April. My last active pill was April 13 and when I started the sugar pills I did get my period in the middle of that week. After that I didn’t start a new pack and I haven’t bled. At all. I had sex the week after the withdrawal bleeding from the sugar pills but I took a test a couple days ago and it’s negative. On May 15th I had sex but obviously I wouldn’t be able to test yet. Should I be thinking pregnancy is the reason for this? Or should I still wait a little longer to see if I get a period? Maybe until the end of this month?