Stopped birth control pills, bled, then started on new pack 1.5 weeks after bleeding.possible to get pregnant? had brown spotting (light) for 4-5 days

Yes: The bleeding indicates your uterus sloughing off the previous months build up of tissue in anticipation of a pregnancy. 10 days post menses (bleeding) means you might have ovulated. You should treat this as if you just started on birth control and avoid unprotected sex for at least a month, one full cycle, after you restarted. Really safe would be two months.