Mucus plug or semen

So I had sex 2 days ago with my bd, about half hour to an hour later I felt loads of wetness come out of me baring in mind I had peed before that, it soaked my shorts - no cramping or anything so I put it down to his fluids just leaking out.

since yesterday I have had some stringy off white discharge and today I went for a 2 hour walk and ended up with cramping. I’m due in 10 days do you think this could be me losing my mucus plug or do you think it could just be my baby dads c*m still coming out of me?

It looked similar to this(had to get one off Google as didn’t take a pic).