Can preeclampsia be possible if no high BP (possible that prescription buspirone/sertraline keeping BP low?) have had occasional protein trace in urine....

Typically no. The buspirone/sertraline will not affect pre-eclampsia. Blood pressures are monitored for elevations. A 24 hour urine collection and analysis is used, rather than a random urine dip. Also, rapid weight gain/swelling, head aches are among the others.