Had a sinus infection and had 2 weeks off all exercise. 2nd gym session back and I've been left with achey hamstrings. Pain is not one specific spot on back of upper leg and comes and goes. Soreness came on later in day, didnt notice at time of workout. Is this likely DOMS / a strain/ too much after 2 weeks off? I didnt jump straight back into my previous programme. Can I run with this ache? Many thanks!! Appreciate it's hard to diagnose over the internet but just after some pointers :)