Anyone taken Lisinopril for high blood pressure?

I was just switched from Toprol to Lisinopril for high blood pressure. I've been on it for about 3 weeks. At first I had no side effects & felt great, but within the last week I've developed a nagging tickling feeling in my throat that gets worse at night. It wakes me up from my sleep and I cough and cough and cough, it gets no better. I usually have to drink a gl of h2o or eat something. Also today I worked out, not strenuous or anything and now I can barely stay awake. Do want to mention that doctors think i MAY have some kind of post viral syndrome, but the things i just listed just started happening since i've taken the lisinopril. Anyone else have similar experience with this medicine? Or any ideas of what else it could be?