ovulation

can a cold cause later ovulation? last month i wasn't ttc because my dh had a vasectomy and didn't get his reversal until the 17th but i still ordered opks and did them just to get an idea and i had a negative on cd 13 then positive on cd 14 and then negative after..i also get ovulation cramping so i'm pretty sure i ovulated on cd 15..my cycles are usually around 29-30 days long occasionally 31 but never longer. this is cd 15 for me and still no positive opk. i had a cold last week..no fever or anything but runny/stuffy nose and a little cough and congestion so did my kids and dh. i'm better now though i believe i got over it last week on like friday..could this be why i haven't had a positive? i didn't do opks before last month so i don't have much to go off of. i don't temp or anything but i get my period on time every month never skipped one..i have other kids and my youngest will be 3 tomorrow. just wondering if i should keep testing or maybe assume i wont ovulate this month? and if i don't, should i expect a period? tia