Good na kayo nag-plano mag-OB check first kasi siya talaga ang best source for your situation! Generally okay ang travel sa second trimester (which you'll be by end of month), pero every pregnancy is different, some moms travel smoothly at 12 weeks, pero iba naman ang experience depende sa flight length, your energy levels, at kung may complications. I'd say mas safe pag after 12 weeks kaya siguro timing-wise okay lang, pero let your OB guide you based sa ultrasound results at how you're progressing, then you can plan accordingly with peace of mind.