getting worried

I'm currently 13 dpo and starting to worry this is not my month. I have been taking hpt (first response and accumed hcg) since 8dpo and they have all been negative. I woke up earlier this morning and temp was initially 98.01 but fell back asleep and temped again when i woke up and thats the one i charted, is there still a chance I could be pregnant or no?