I had substantial pain and bruising and what felt like a hard lump under the skin?

Approximately 1.5 weeks ago I slipped in the shower, and landed in such away as the vertical shower door rim impact my left buttock – I had substantial pain and bruising and what felt like a hard lump under the skin. The bruising is now quite dark and seems normal, but the hard lump was occasionally painful when sitting ‘on’ it in certain positions on hard surfaces. Today I sat on an exercise bike and when I began to pedal it felt as if the lump dislodged or tore or moved (I can’t explain it any better than this – something definitely changed mechanically) and the pain became quite severe – I couldn’t continue on the cycle, and then walking was also painful. It feels like a burning sensation just under the surface of the skin, exactly at the location of this lump. Even very gentle pressure on the area causes a burning pain. It may be worth noting that the lump is not exactly underneath the bruise but was definitely caused by the same injury. There is also no new bruising in the area. It also does not seem to be muscular at all – as I mentioned, it feels like it is just under the skin, but also when I tense the muscles in that area there is no pain. I am mostly concerned because I have to fly long distance in 3 days and hope I will be able to cope with over the counter pain medication – or, does this seem like something I should see a doctor for before I travel?

Age: 38
Male
Medications: none