Second time happening ..☹️

So since I’ve been pregnant I’ve literally had to spit every second , like I legit walk around with a spit cup . So today when I went to spit , I spit out a small clot of blood . This has happen a time before as well . I’ve thrown up blood in the past ( not clots ) doctors said it was normal . I don’t feel any pain or any different , just concern if it’s normal or has happened to anyone before ?

My mom said it could be because my nose / throat is dry and due to my allergies ☹️