BFP but now worried...help!!!

Laura • One son 11 years old had Ectopic and lost my baby on 12th Feb2014 ❤️ 2nd ectopic baby lost Nov2014, expecting Feb2017
I got a BFP on Friday night and Saturday morning. Having cramps for a week now had pinkish discharge yesterday and today woke up to brown discharge :( doc has booked me in for bloods n early scan this week. I took another clearblue digital that said I'm pregnant about 1-2 (4wks pregnant) am I over reacting or should I prepare for the worst??