Could I be pregnant?

I was supposed to have my implant taken out months ago, as it was the end of the three years. My gyno pushed back my appointments multiple times, so now I go June 4th. I had sex on the 19th. No other forms of birth control. He finished inside me. I missed my period, then on the 23rd, I had spotting. It was different than normal blood so I looked it up and it said implantation bleeding. I took a test tonight and it came up negative. Could I be pregnant? Is it too soon to test?