"Pressure paramounted when I was impeded from attending the final examinations of the second semester"
The only citation for paramount as a verb in the OED is dated 1699 (obsolete and rare!) ... (http://www.oed.com/view/Entry/137536?isAdvanced=false&result=2&rskey=7cqC57&)
Depending on the sense you want you could use build, intensify or become intolerable:
Pressure built / intensified / became intolerable when I was impeded from attending the final examinations of the second semester.
As @Dan explained, paramount is not used as a verb. And a lot of good suggestions have been offered to replace it. My 2 cents is the noun pressure is a good choice, but the noun stress works better in your context which means:
A state of mental or emotional strain or tension resulting from adverse or demanding circumstances:
I was under great (or tremendous, unbearable or intolerable) stress when I couldn't attend the final examinations of the second semester.
Using the adjective great is far more popular than using tremendous, unbearable or intolerable. Also, you could consider replacing was under great stress with felt stressed out.
Using Stress increased exponentially, sharply or dramatically when... or Stress became unbearable when..., etc is another option if you want to use stress as a subject.
As Simon White commented to Dan's answer, was impeded is not idiomatic especially when it is used without by an agent at the end of the sentence.
[Oxford Online Dictionary, Ngram Viewer]