Very faint line or am I seeing things?

Hi Ladies,
I'll spare you the long medical details as to why I am a little shocked by this and I kind of think I am seeing things. I took an Internet test stick the other day and it was negative but after throwing up last night 'thinking' it was food poisioning I grabbed a first response early result test on my way to work ... Again I have to be seeing things. I have no other symptoms and  irregular cycles. I had cramping on Saturday and slight bleeding not Sunday am but nothing since. Appreciate any insight you might have