Am I pregnant

I've had my period but I'm still stressing that i might be pregnant I've had 3 periods since but the first one stopped for 5 hours and then started normally again the second one was heavy for 5 days and the third started normal spotted half way through then started normal again and usually it goes for 4 days the first two days heavy the last 2 days spotting I've had 5 negative pregnancy tests after first period. Am I stressing over nothing?