I doubt it. I think that would only cause a slight increase in pressure, unless it's completely clogged, then I guess it could cause a huge pressure increase.
Mysterious loss of coolant is the number one sign for a cracked head
The next symptom is milky oil.
If I were you, I'd drain the oil to know for sure. The coolant in the oil, if not fixed can ruin your bottom end & make cause a head job to turn in to a rebuild.