Welcome to HCM.
You were present with light brown bleeding for 3 days with nausea
.Spotting or bleeding may be due to early implantation
imbalance. As you got negative blood test
on June 26th (2wks after spotting),the chance of pregnancy
is less likely.
you can do a USG for evaluating underlying pathology with exclusion of pregnancy along with some hormonal study like thyroid
level, LH/FSH etc.
After doing all investigations,you can consult with your doctor.
Take healthy protein rich diet, Vit-E & folic acid
supplements, calcium & other nutrients,avoid stress
do light exercise and proper sleep.