Tachycardia (high heart rate) and herpes meds

Im not sure whether this is the right place to post this but thought it was worth a shot. Ive had HSV2 since september and was unfortunatle enough to have frequent outbreaks. Just before christmas i bit the bullet and got myself put onto acyclover to supress it. However, I've been suffering with tachycardia for several weeks now with a heart rate ranging from normal to 140 resting. My ECG didnt show any concerns and im currently waiting for repeat blood tests as the first one showed a low phosphate. Could this be the cause of the high heart rate? It started around2 weeks after i started taking the tablets (its hard to remember exactly though) but ive been off these tablets for almost 3 weeks now? Surly it qould have settled down by now? Ive ready that acyclovir can cause low phosphate but theres hardly anything about this on google so any advice is massivly appreciated cos this is starting to get to me now. Its not painful but a strange and worrying feeling. 

Regarding the herpes, yes it's becoming manageable yet still annoying as hell. Please consult with your Dr regarding your heart rate.

I have been consulting with my doctor, who's been running some blood tests. I just thought I'd ask incase anyone else had experienced something simular. Thank you for your reply 

My blood pressure has always been normal. At first I was on acyclovir, then I started taking valtrex 1 gram for suppressive therapy, my heart rate is normal. Did you have any issues with your heart rate prior to this?

Sorry for the delay with my reply. No i have never noticed any heart issues before now. Im not sure about blood pressure as i only had that checked when i saw my GP about the rapid heart rate. He's run bloods and an ECG wh9ch came back normal and im waiting for urine and a 24 hr ECG now. He doesnt seem to think its linked to the herpes but im not convinced. Esspecially as my asthma is worse during an outbreak which no doctor seems to know the reason behind.